1-8 An Introduction to Equations

• Equation – a mathematical sentence that contains an equal sign (=).

• Open sentence- a statement with one or more variables. – Neither true nor false until the variables

have been replaced with specific values.

Solution – a value for the variable that makes an equation true.

True, False or Open?1. 24 + 18 = 20 + 22

2. 7 ∙ 8 = 54

3. 2x – 14 = 54

4. 3y + 6 = 5y - 8

Is the given number a solution?

1. 32 = 2x + 1; x = 6

2. 6m – 8 = -15; m = 1/2

Write an equation1. The difference of a number and 7 is 8.

2. 6 times the sum of a number and 5 is 16.

3. Joel is 11 years older than Mary. Write an equation that relates the age of Joel and the age of Mary

4. A computer programmer works 40 hours per week. What is an equation that relates the number of weeks w that the programmer works and the number of hours h that the programmer spends working.