Solving Equations

Sam makes $400 per week plus $20 commission on each new cell phone plan she sells. What is the equation that determines how many new plans she sold to earn $680 last week?

• 400p + 20 = 680

• 400 + 20p = 680

• 400p + 20P = 680

• 420p = 680

Eric has a dog walking business. He charges $13 per dog he walks and $6 for the water he buys for the dogs. If he made $97 on Monday, what is the equation you would use to find the number of dogs he walked on Monday?

• 19d = 97

• 6d + 13 = 97

• 6 + 13d = 97

• 13d + 6d = 97

In addition to dog walking, on Tuesday Eric made $45 dog sitting at one of his customer's homes. If he made $168 on Tuesday, write an equation to find the number of dogs e walked that day. (Remember: he charges $13 per dog).

• 58d = 168

• 45d + 13 = 168

• 45d + 13d = 168

• 45 + 13d = 168

Rena swims every day. She burns approximately 10.6 calories per minute when swimming and about 15 total calories warming up before she swims. Write an equation to find how many minutes Rena must swim to burn 205.8 calories.

• 10.6c + 15 = 205.8

• 15.6c = 205.8

• 10.6 + 15c = 205.8

• 10.6c + 205.8 = 15

A cell phone company charges $10 per month for up to 500 text messages and $0.15 for each additional text message. Stanley was charged $14.50 last month for text messages. Write an equation to find the number of text messages over 500 he sent and received last month.

• 10.15m = 14.50

• 10m + 0.15 = 14.50

• 10 + 0.15m = 14.50

• 0.15m = 14.50

Solve the equation.

3x + 2 = 26

• 8

• 9 ¹/3

• 6

• 72

Solve the equation.

4c - 18 = 6

• -3

• 8

• 6

• -48

-7x + 3 = 17

• 2

• -²⁰/7

• 8

• -2

1/2n + 3 = -9

• -12

• -6

• -24

• -3

3 + 4g = 11

• 2

• ¹⁴/4

• 4

• ¹¹/7