Chapter 4 Equations and Inequalities

Which property justifies the work in solving this equation?

• Addition Property of Equality

• Multiplication Property of Equality

• Commutative Property of Addition

• Subtraction Property of Equality

Sally bought three candy bars for a total of $18.00. How much did each candy bar cost? Write an equation to solve this problem. Use c as your variable.

• 18c=6

• c + 6= 18

• c +18 = 6

• 3c=18

Translate: 
Four times a number plus six is 30.

• 4 + 6 = 30

• 4x + 6 = 30

• x + 4 times 6 = 30

• 30 = 4x

What inequality does the number line graph represent?

• x >= 3

• x > 3

• x < -3

• x <= 3

• A

• B

• C

• D

When solving an equation, our goal is to:

• add all the numbers together.

• use a calculator.

• eat lunch.

• isolate the variable to solve.

-2(x + 3) - 5 = 11

• x = - 11

• x = 2

• x = 11

• x = -2

5x - 7 = 8

• x = 1/5

• x = 3

• x = -3

• x = 15

A phone company charges a sign-up fee of $3.50, plus $x for every hour the phone is used. If Brian talked on the phone for 12 hours and paid a total of $75.50, which of the following equations can be used to find, x, the hourly rate of the phone plan?

• 3.50 + x = 75.50 

• 3.50 - x = 75.50 

• 75.50 + 12x = 3.50 

• 3.50 + 12x = 75.50

Solve for t. (Use the image to identify the correct inequality and graph.)

• A

• B

• C

• D