Solving Multi-Step Equations

4-5

Objective

Today you will solve equations involving more than one operations.

When solving multi-step equations, you need to work BACKWARDS with order of operations

P ( )

E (x2)

M (X)

D (÷)

A (+)

S (-)

Solve Multi-Step Equations 11x – 4 = 29 + 4 = +4

11x = 33 ÷11 = ÷11

x = 3

P ( )

E (x2)

M (X)

D (÷)

A (+)

S (-)CHECK: 11x – 4 = 29

11 (3) – 4 = 29 33 – 4 = 29 29 = 29

a + 7 = 5 8

a + 7 = 5(8) 8

a + 7 = 40 - 7 = - 7

a = 33

( )8 CHECK: 33 + 7 = 5 8

40 = 5 8

5 = 5

Equations with Negative Coefficients

9 - t = -34

Identity Property: t = 1t

Definition of Subtraction

9 – 1t = -34

9 + (-1t) = -34-9 -9 Subtract 9 from both sides

(-1t) = -43 Simplify

(-1t) = -43Division Property of Equality

-1 = -1 1t = 43 Simplify

CHECK: 9 – 43 = -34 -34 = -34

Combine Like Terms Before Solving2x + x – 27 = 3

2x + 1x = 3x

3x – 27 = 3

Combine like terms

Rewrite

3x – 27 = 3+ 27 = +27

Add 27 to each side.

3x = 30 3 3

X = 10

Divide each side by 3.

Simplify

CHECK: 2x + x – 27 = 3 2(10) + 10 -27 =3 20 + 10 – 27 = 3 30 – 27 = 3 3 = 3

YOUR TURN 1) 2a – 6 = 4

2) n + 2 = 15 -2

3) -15 – b = 44

4) 4 -9c + 3c = 58

a = 5

n = -32

b = -59

c = -9

Thought of the Day!

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