handbook and notes -...
TRANSCRIPT
Algebra 1
Handbook and Notes
Student Name: Class: Year:
Algebra 1—Handbook and Notes
2
Algebra 1—Handbook and Notes
3
Class Goals Our goals for the Algebra 1 course include:
1. Successfully preparing for and passing the End of Instruction Exam 2. Successfully preparing for the next level of math:
a. Geometry b. Algebra 2 c. Precalculus d. Math Finance
3. Successfully preparing for the ACT Exam 4. Learn how to apply math skills and concepts to real-world situations
Student Work Goals Doing quality work is extremely important in both the academic world (i.e., school) and the real-world (i.e., home and work). Therefore, everything we do in class should include these characteristics:
1. Neatness—our work is organized and easy to read 2. Detail—our work is clear in meaning and not vague 3. Accuracy—our work is correct and free from errors
Desired Employee Skills The following three skills were identified in the book by Bill Coplin entitled 10 Things Employers Want You to Learn in College. Below are three of those skills employers will be looking at as they consider hiring you for a job opening. These same skills will also help you as you continue to pursue your education in high school. Therefore, high school is a great time to begin practicing these skills.
1. Work well with others a. Be kind, friendly, and patient with others b. Be a team player
2. Know your numbers a. Working with data is important in every work field
3. Be responsible for yourself a. Have strong motivation b. Be ethical (i.e., do the honest and right thing) c. Have good time-management skills (turn projects/assignments in by their
deadline)
Algebra 1—Handbook and Notes
4
Class Notes Example The importance of taking class notes in a math course:
1. Allows the student to practice doing the problems with the instructor 2. Creates a resource of information and examples for the student to refer back to when
doing assignments and studying 3. Allows the teacher to help the student when he or she has extra questions 4. Shows that the student is putting effort into their own learning.
The example below shows what high quality notes should look like. Notice, they also meet our Student Work Goals in that they are neat, detailed, and accurate.
3.3 Solving Linear Equations
Sherry Walker 4th Hour 10/3/14
3.3
Solving Linear Equations:
a. Get 𝒙 by itself on one side of the equal sign
b. Always do the opposite of what is being done to both sides of the
equation
c. Work in reverse order of operations or think of it as “do what is with
the variable last”.
Example 1:
Solve for 𝑥.
3𝑥 + 4 = 16
−4 −4
3𝑥 = 12
3 3
𝑥 = 4
Example 2:
A plumber charges $35 for a service call fee and $8 per hour for repairs. Write and
solve an equation for how many hours the plumber worked if he charges a
total of $83.
83=8x+35
-35 -35
48=8x
8 8
X=6
The plumber worked a total of six hours when charging $8 per hour and
an initial $35 service call fee.
Algebra 1—Handbook and Notes
5
Homework Assignment Example Homework guidelines:
1. You must include your complete heading. 2. You must show detailed work when solving problems. 3. Application problems (i.e., word problems) require the answer to be written as a
complete sentence with a subject, verb, solution, and proper punctuation.
Sherry Walker
4th Hour
10/3/14
3.3
1. 1
3 𝑥 − 6 = −8
+6 +6
1
3 𝑥 = −8
(3)1
3 𝑥 = −8(3)
𝑥 = −24
2. 5𝑥 + 3(𝑥 + 4) = 28
5𝑥 + 3𝑥 + 12 = 28
8𝑥 + 12 = 28
−12 −12
8𝑥 = 16
8 8
𝑥 = 2
3. 𝑐 = 12(𝑥) + 45
𝑐 = 12(4) + 45
𝑐 = 48 + 45
𝑐 = 93
The electrician would charge a total of $93 for working four hours at $12 an hour
and charging a $45 service fee.
4.
Algebra 1—Handbook and Notes
6
Resources Teacher Ease Teacher Ease is the website you will log into to access assignments, videos, tutorials, and grades. Teacher Ease can be accessed at the following address:
http://www.teacherease.com Holt Online Textbook and Assignments You can access your entire textbook, worksheets, tutorial videos directly on the textbook company’s website. Log on below with the login and password you have been provided at the address below:
http://my.hrw.com Chromebook Apps It is recommended that the following Google Chrome applications be installed on your Chromebook:
1. General Apps a. Google Drive b. Google Docs c. Google Sheets d. Google Calendar e. Google Search
2. Math Apps a. Desmos Graphing Calculator b. TeX equation editor c. Daum Equation Editor (As a backup to TeX equation editor) d. GeoGebra
Calendars
1. District Calendar Link
2. High School Events Calendar Link
3. Algebra 1 Calendar Link http://www.google.com/calendar/feeds/cushing.k12.ok.us_sfl6jo41h8jhllds28p5dq1k2s%40group.calendar.google.com/public/basic
Algebra 1—Handbook and Notes
7
End of Instruction (EOI) Exam Examples The End of Instruction (EOI) Exam will be made up of not only multiple choice questions, but also constructed response questions that will require students to:
justify their steps in solving a problem
show their work
explain their steps in solving a problem
explain the meaning of the answer using complete sentences
sketch functions by hand Examples of each of these types of questions are shown below. Multiple Choice
1. Consider this quadratic equation. 𝑥2 + 2𝑥 − 48 = 0
What are the solutions to the equation? (A.REI.4b)
A 6 and −8
B 8 and −6
C 4 and −12
D 12 and −4
Constructed Response
2. A generator contains 20 gallons of gasoline. It consumes the gasoline at a rate of 0.9 gallons per hour. The generator fuel light turns on when the gasoline level drops to 2 gallons. The equation shown can be used to determine the number of hours, h, the generator will run before the fuel light turns on.
20 − 0.9ℎ = 2 Solve the equation for ℎ to determine the number of hours before the fuel light turns on. Justify why each step was used to solve the equation. (A.REI.1)
Notice
Algebra 1—Handbook and Notes
8
3. Solve the following system of equations. Find the ordered pairs that satisfy both
equations. (A.REI.11) 2
3𝑥 +
3
5𝑦 = 3
1
2𝑥 −
3
5𝑦 = 4
Show your work.
4. Miranda is training for a 26-kilometer race to raise money for her favorite charity. The first week of training, she runs 6 kilometers. She then adds 2 kilometers to her training run each week.
She uses the equation t = 2w + 4, where t represents the total kilometers ran and w represents the number of weeks.
Solve the equation for w and explain the operation used in each step. (A.REI.1)
In which week of her training program will she reach 26 kilometers?
Notice
Notice Notice
Algebra 1—Handbook and Notes
9
5. The owner of a new theme park needs to determine what ticket price will result in the largest attendance and therefore the maximum revenue. The predicted daily revenue for a large theme park is given by the function 𝑓(𝑥) = 40,000𝑥 − 250𝑥2, where x is the admission price in dollars per person. Find the 𝑥-intercept(s) and the vertex of the graph of 𝑓(𝑥). (A.IF.4) Show your work. 𝑥-intercepts
Vertex Explain the meaning of the x-intercept(s) and the vertex in this situation.
Sketch a graph of 𝑓(𝑥) on this coordinate plane.
Notice
Notice
Notice
Algebra 1—Handbook and Notes
10
Introduction Unit Order of Operations
1. Grouping Symbols—parentheses: ( ), absolute value: | |, radicals: √ 2. Powers—exponents 3. Multiplication/Division left to right 4. Addition/Subtraction left to right
Absolute Value—the distance that a number is from zero (the origin) on the real number line Ex. |3| = 3 Ex. |−3| = 3 Algebraic Expression
A collection of numbers, variables, and operations
Coefficient Exponent 3𝑥2 + 5
Variable Operation Constant
Coefficient—the number in front of a variable Exponent—a number written as a superscript that represents the number of times the base is
used as a factor Variable—a letter used to represent one or more numbers Operation—addition, subtraction, multiplication, division Constant—a plain number with no variable
Distance Formula 𝑑 = 𝑟𝑡 𝑑 = distance 𝑟 = rate 𝑡 = time
Simple Interest Formula 𝐼 = 𝑝𝑟𝑡 𝐼 = simple interest 𝑝 = principal (initial amount) 𝑟 = interest rate 𝑡 = time in years
Algebra 1—Handbook and Notes
11
Expressions, Equations, and Inequalities Expression—a collection of numbers, variables, and or operations Ex. 3𝑥 + 𝑦 Equations—has an equal sign (=) between two expressions Ex. 2𝑥 + 4 = 19𝑥 − 7 Inequality—has an inequality symbol (<, >, ≤, ≥) between two expresions Ex. 16𝑚 ≥ 96
Translating Verbal Phrases
“is” (also verbs such as “are” and “will be”) —means =
“more than” and “and”—usually mean addition
“less than” and “difference”—mean subtraction
“of”—usually means multiplication
“3 feet per second”—usually can be written as 3𝑥
Algebra 1—Handbook and Notes
12
Real Numbers
real number—all rational and irrational numbers Examples: every number that exists
rational number—a number 𝑎
𝑏 where 𝑎 and 𝑏 are intergers and 𝑏 ≠ 0
Examples: 2, −.45, −2
3
irrational number—a number that cannot be written as a quotient of two integers (i.e., a number that cannot not be written as a fraction
Examples: √17, 𝜋, −√3 Square Roots
radical symbol
√𝑎 radicand
square root—if 𝑏2 = 𝑎, then 𝑏 is a square root of 𝑎. Example: 32 = 9 and (−3)2 = 9, so 3 and −3 are square roots of 9. perfect squares—the square of an integer
Examples: 1, 4, 9, 16, 25, 36, 49, 64, 81, 100, 121, 144, 169, 196, 225
Algebra 1—Handbook and Notes
13
Solving Linear Equations Tips for Solving Linear Equations:
Get 𝑥 by itself on one side of the equal sign.
Always do the opposite operation that is being done and do it to both sides of the equation.
Work in reverse order of operations. (Another way to think of this is to “do what’s with the variable last.”)
Word Problem Key Words “is” (also verbs such as “are” and “will be”) —means = “more than” and “and”—usually mean addition “less than” and “difference”—mean subtraction “of”—usually means multiplication “3 feet per second”—usually can be written as 3𝑥 Plumber Problem Example A local plumber charges customers a $35 service call fee for diagnosing a plumbing problem and $8 per hour for labor. Write an equation for the total cost of the plumber’s charges.
Total Cost Number of Initial Service Hours Worked Call Fee
𝑐 = 8𝑥 + 35
“is” (verb) “$8 per hour” Rates, Ratios, and Proportions Rate—compares different units by division
Examples: miles per hour miles
hour cost per person
cost
person
1 yard = 3 feet can be written as:
1 yard
3 feet or
3 feet
1 yard
Ratio—compares same units by division
Algebra 1—Handbook and Notes
14
Functions Function – a rule that establishes a relationship between two quantities.
“for every input, there is exactly one output” ← KEY
input – what you plug into an equation output – what comes out of an equation (essentially, your answer) domain – all of the input values (what you can plug into the equation) range – all of the output values (think of it as your “range” of answers)
Domain Inputs
𝑥 Independent variable
Range
Outputs 𝑦
Dependent variable
Function Notation 𝑓(𝑥) = 𝑦 Example: 𝑦 = 3𝑥 + 5 𝑓(𝑥) = 3𝑥 + 5 Function notation Types of Functions (In Algebra 1)
1. Linear Function—a line; increases by a constant rate of change (same slope)
𝑓(𝑥) = −4𝑥 + 7
2. Absolute Value Function—a “v” shape; can open up or down
𝑓(𝑥) = 2|𝑥 + 3| − 6
3. Piece-wise Function—made of different “pieces”, each with a different domain
f(x) = {x − 3, if x ≥ 0
−5x + 2, if x ≤ 0
4. Exponential Function—an exponential curve; increases or decreases by a multiply (i.e.,
percentage)
𝑓(𝑥) = 3 ∙ 5𝑥
5. Quadratic Function—a parabola; can open up or down
𝑓(𝑥) = 4𝑥2 + 7𝑥 − 1
or
or
or
Algebra 1—Handbook and Notes
15
Linear Functions Linear Function
The 𝑥 and 𝑦 of a linear equation are: a. To the first power b. Not multiplied together c. Not in the denominator
Has a graph that forms a straight line
Has the same slope (i.e., rate of change) between each point on the line
Can be written in any of the three following forms: Forms of Linear Equations
Standard Form 𝐴𝑥 + 𝐵𝑦 = 𝐶
Slope-Intercept Form 𝑦 = 𝑚𝑥 + 𝑏
Point-Slope Form 𝑦 − 𝑦1 = 𝑚(𝑥 − 𝑥1)
Equations of Horizontal and Vertical Lines
The graph of 𝑦 = 𝑏 is a horizontal line. The line passes through the point (0, 𝑏).
The graph of 𝑥 = 𝑎 is a vertical line. The line passes through the point (𝑎, 0)
Parent Graph of a Linear Function
𝑦 = 𝑥
𝑥 𝑦 −2 −2 −1 −1 0 0 1 1 2 2
Algebra 1—Handbook and Notes
16
Slope Formula
Slope = rise
run
𝑚 =𝑦2 − 𝑦1
𝑥2 − 𝑥1
Classification of Lines by Slope
A line with positive slope rises from left to right.
A line with negative slope falls from left to right.
A line with zero slope is horizontal.
A line with undefined slope is vertical.
𝑚 > 0 𝑚 < 0 𝑚 = 0 𝑚 is undefined
Methods of Graphing Linear Functions
1. Table a. Make and input-output table with at least five values for 𝑥. b. Plot the ordered pairs on a coordinate plane. c. Draw a line through the points with a ruler.
2. Find the 𝑥-intercept and the 𝑦-intercept a. Plug in zero to 𝑥 and solve for 𝑦 to get the 𝑦-intercept. b. Plug in zero to 𝑦 and solve for 𝑥 to get the 𝑥-intercept. c. Plot the two intercepts on a coordinate plane. d. Draw a line through the points with a ruler.
3. Slope-Intercept Form a. Rewrite the equation in slope-intercept form: 𝑦 = 𝑚𝑥 + 𝑏. b. Plot the 𝑦-intercept using the 𝑏-value. c. Plot several other points of the line using the slope (𝑚) to count rise over run
from the y-intercept. d. Draw a line through the points with a ruler.
Algebra 1—Handbook and Notes
17
Slope-Intercept Form slope 𝑦-intercept
𝑦 = 𝑚𝑥 + 𝑏
rate of change original amount
Parallel and Perpendicular Lines
Parallel Lines
1. Never intersect 2. Have the same slope
a. 𝑦 = 2𝑥 + 7 b. 𝑦 = 2𝑥 − 3
Perpendicular Lines
1. Intersect at a right angle (i.e., 90o) 2. Have the opposite reciprocal slope;
Their product is −1 a. 𝑦 = 3𝑥 + 9
b. 𝑦 = −1
3𝑥 + 2
Algebra 1—Handbook and Notes
18
Writing Linear Equations Forms of Linear Equations
1. Standard Form 𝐴𝑥 + 𝐵𝑦 = 𝐶
2. Slope-Intercept Form 𝑦 = 𝑚𝑥 + 𝑏
3. Point-Slope Form 𝑦 − 𝑦1 = 𝑚(𝑥 − 𝑥1)
You need two things to write the equation of a line:
1. slope 2. 𝑦-intercept
Writing the equation of a line:
1. Find the slope (𝑚) using the slope formula. 2. Plug the slope and an ordered pair that is on the line into 𝑦 = 𝑚𝑥 + 𝑏 and solve for 𝑏. 3. Write the equation of the line by plugging in the values of 𝑚 and 𝑏 to 𝑦 = 𝑚𝑥 + 𝑏.
Create a Line of Best Fit
1. Make a scatter plot of the data. 2. Draw a line of best fit. 3. Pick two points on the line and find the slope of the line using the slope formula. 4. Plug the slope and an ordered pair that is on the line into 𝑦 = 𝑚𝑥 + 𝑏 and solve for 𝑏.
Algebra 1—Handbook and Notes
19
Linear Inequalities Inequality Symbols
< Less than
> Greater than
≤ Less than or equal to
≥ Greater than or equal to Graphing Linear Inequalities
1. Graph the inequality as you would an equation a. Used a dashed line for < and > b. Used a solid line for ≤ and ≥
2. Shade the side of the line with all the solutions to the inequality. a. Option 1: Test a point on either side of the line to determine if the point is a solution. If
the point is a solution, shad that side of the line. b. Option 2: If the inequality is in slope-intercept, shade according to the inequality
symbol. i. Example 1: For 𝑦 < 2𝑥 + 3, shade below the line because that is where “𝑦 is
less than” than the line. ii. Example 2: For 𝑦 > 2𝑥 + 3, shade above the line because that is where “𝑦 is
greater than” the line.
Graphing Linear Inequalities
Shaded Below “less than or equal to 𝑦”
𝑦 ≤ 2𝑥 + 3
Shaded Above “greater than y”
𝑦 > 2𝑥 + 3
Algebra 1—Handbook and Notes
20
Systems of Linear Equations Methods for Solving Linear Systems
1. Graphing a. Write each equation in slope-intercept form: 𝑦 = 𝑚𝑥 + 𝑏. b. Graph both equations on the same coordinate plane. c. The point (i.e., ordered pair) where the lines intersect is the solution to the linear
system. d. Write your answer as an ordered pair.
2. Substitution a. Solve one of the equations for one of its variables. When possible, solve for a
variable that has a coefficient of 1 or −1. b. Substitute the expression from Step A into the other equation and solve for the
other variable. c. Substitute the value from Step B into the revised equation from Step A and
solve. d. Write your answer as an ordered pair.
3. Elimination/Combination a. Arrange the equations with like terms in columns (such as Standard Form). b. Multiply one or both of the equations by a number to obtain coefficients that are
opposites for one of the variables. c. Add the equations from Step B. Combining like terms will eliminate one variable.
Solve for the remaining variable. d. Substitute the value obtained in Step C into either of the original equations and
solve for the other variable. e. Write your answer as an ordered pair.
Number of Solutions of a Linear System
Lines Intersect One solution 𝑥 = 𝑎 and 𝑦 = 𝑏
Lines are parallel No solution “False Statement”
Lines coincide Infinitely man solutions “True Statement”
Algebra 1—Handbook and Notes
21
Exponents Rules of Exponents
1. Product of Powers—to multiply powers with the same base, add the exponents
𝑥2 ∙ 𝑥5 = 𝑥7
2. Power of a Power—to find a power of a power, multiply the exponents.
(𝑦3)4 = 𝑦12
3. Power of a Product—to find a power of a product, multiply the exponents of all the factors
(𝑥2𝑦𝑧4)5 = 𝑥10𝑦5𝑧20
4. Quotient of powers—to divide powers with the same base, subtract the exponents
𝑚5
𝑚3= 𝑚2
5. Power of a Quotient—to find the power of a quotient, multiply the exponents of all the factors
(𝑎4
𝑏3)
2
=𝑎8
𝑏6
6. Zero Exponent—all nonzero numbers to the zero power is 1
50 = 1
7. Negative Exponent—take the reciprocal and switch the sign of the exponent
𝑎−3 =1
𝑎3 or
1
𝑎−3= 𝑎3
Algebra 1—Handbook and Notes
22
Adding, Subtracting, & Multiplying Polynomials Polynomial—a monomial or the sum of monomials
1. Monomial—a number, variable, or a product of a number and one or more variables Examples: 7, 3𝑥, and 5𝑚3
2. Binomial—the sum of two monomials Examples: 2𝑥 + 4 and 9𝑦3 − 1
3. Trinomial—the sum of three monomials Example: −2𝑥2 − 3𝑥 + 6 Standard form of a polynomial:
Leading coefficient Degree Constant term
2𝑥3 + 5𝑥2 − 4𝑥 + 7
Algebra 1—Handbook and Notes
23
Factoring Polynomials Factoring Cloud
1. Pull out the Greatest Common Factor (GCF) if possible. 2. Continue factoring by:
a. Difference of two squares—two terms b. Trinomial (British Method)—three terms c. Grouping—four terms
3. Check to see if it will factor again.
Algebra 1—Handbook and Notes
24
Absolute Value Functions Absolute Value Function
Has a graph that looks like a “v”
Parent Graph of an Absolute Value Function
𝑦 = |𝑥|
𝑥 𝑦 −2 2 −1 1 0 0 1 1 2 2
Is “like” the slope of Opens up if + Shifts the graph up or down. The right side of the graph Opens down if –
𝑦 = 𝑎|𝑥 − ℎ| + 𝑘 Shrinks if |𝑎| > 1 Shifts the graph left or right Stretches if 0 < |𝑎| < 1 (opposite of what you see).
(ℎ, 𝑘) is the vertex.
Algebra 1—Handbook and Notes
25
Quadratic Functions
Parent Graph of a Quadratic Function
𝑦 = 𝑥2
𝑥 𝑦 −2 4 −1 1 0 0 1 1 2 4
Forms of Quadratic Functions
1. Standard Form 𝑦 = 𝑎𝑥2 + 𝑏𝑥 + 𝑐
2. Vertex Form 𝑦 = 𝑎(𝑥 − ℎ)2 + 𝑘
3. Intercept Form 𝑦 = 𝑎(𝑥 − 𝑝)(𝑥 − 𝑞)
Graphing Standard Form 𝒚 = 𝒂𝒙𝟐 + 𝒃𝒙 + 𝒄
The x-value of the vertex is 𝑥 = −𝑏
2𝑎
The axis of symmetry is the vertical line 𝑥 = −𝑏
2𝑎
Steps for graphing:
1. Find the vertex using 𝑥 = −𝑏
2𝑎
2. Make a table with points on either the left or right of the vertex and make a table. Graphing Vertex Form 𝒚 = 𝒂(𝒙 − 𝒉)𝟐 + 𝒌
The vertex is (ℎ, 𝑘)
The axis of symmetry is 𝑥 = ℎ Steps for graphing:
1. Find the vertex using (ℎ, 𝑘). 2. Make a table with points on either the left or right of the vertex and make a table.
Algebra 1—Handbook and Notes
26
Graphing Intercept Form
The 𝑥-intercepts are 𝑝 and 𝑞.
The axis of symmetry is halfway between (𝑝, 0), and (𝑞, 0). Steps for graphing:
1. Plot the 𝑥-intercepts using (𝑝, 0) and (𝑞, 0). 2. Find the axis of symmetry and vertex halfway between the 𝑥-intercepts. 3. Plug in 𝑥-value of the axis of symmetry into the function to find the 𝑦-value of the
vertex. Methods for Solving Quadratic Equations
1. Graphing a. Set the equation equal to zero. b. Write and graph the related function c. Identify the 𝑥-intercepts (i.e., zeros)
2. Factoring a. Set the equation equal to zero. b. Factor. c. Set each factors equal to zero and solve for 𝑥.
3. Square Root Method a. Isolate the 𝑥2 or (𝑥 − ℎ)2 b. Take the square root of both sides
4. Completing the Square
a. Create a perfect square trinomial by finding the 𝑐-value using (𝑏
2)
2
.
b. Factor the perfect square trinomial. c. Solve for 𝑥 by using the square root method.
5. Quadratic Formula
𝑥 =−𝑏 ± √𝑏2 − 4𝑎𝑐
2𝑎
6. Synthetic Division (Algebra 2 concept)
Algebra 1—Handbook and Notes
27
Exponential Functions Exponential Function
Has a graph that is curved
The graph increases or decreases by a multiple (percentage) Exponential Growth
𝑦 = 𝑎𝑏𝑥 𝑎 is the initial amount. 𝑟 is the growth rate.
𝑦 = 𝑎(1 + 𝑟)𝑡
1 + 𝑟 is the growth factor. 𝑡 is the time period.
𝑎 > 0 and 𝑏 > 1
Exponential Decay
𝑦 = 𝑎𝑏𝑥 𝑎 is the initial amount. 𝑟 is the decay rate.
𝑦 = 𝑎(1 − 𝑟)𝑡
1 + 𝑟 is the decay factor. 𝑡 is the time period.
𝑎 > 0 and 0 < 𝑏 < 1
{
{
Algebra 1—Handbook and Notes
28
Piece-wise Functions Graphing a Piece-wise Function:
1. Make a table for each “piece” of the function. 2. Plot the points for each piece on the same coordinate plane. 3. Use and appropriately at the end(s) of each piece.
Piecewise Function
𝑓(𝑥) =2𝑥,
𝑥 − 4, 𝑖𝑓 𝑥 > 1𝑖𝑓 𝑥 ≤ 1
𝑓(𝑥) = 2𝑥 𝑓(𝑥) = 𝑥 − 4 x y x y
1 2 1 −3
0 0 2 −2
−1 −2 3 −1
−2 −4 4 0