7th grade Solving Equations

Checking Solutions

100

Jimmy James was solving this equation. Check his work to see if he is right. If incorrect, show the correct answer.

-12 = x - 14 

-12 - (-14) = x - 14 - 14

x = -26

Incorrect

-12 = x -14

+14    +14

2 = x

200

Jimmy James was solving this equation. Check his work to see if he is right. If incorrect, show the correct answer.

-5 + x/10 = 0 

-5 +5 + x/10 = +5

x/10 = 5

x = 50

Correct!

300

Jimmy James was solving this equation. Check his work to see if he is right. If incorrect, show the correct answer.

8x + (-1) = 33 

8x + (-1) - 1 = 33 - 1

8x = 32

x = 4

Incorrect: 

8x + (-1) = 33 

8x + (-1) + 1 = 33 + 1

8x = 34

x = 4.25

400

Jimmy James was solving this equation. Check his work to see if he is right. If incorrect, show the correct answer.

11c - 24 = -2 

11c - 24 + 24 = -2 + 24

11c = 22

c = 2

Correct!

500

Jimmy James was solving this equation. Check his work to see if he is right. If incorrect, show the correct answer.

-3(2x - 8) + 10x = 16 

-6x + 24 + 10x = 16

4x + 24 = 16

4x + 24 - 24 = 24 - 16

4x = 8

x = 2

Incorrect: 

-3(2x - 8) + 10x = 16 

-6x + 24 + 10x = 16

4x + 24 = 16

4x + 24 - 24 = 16 - 24

4x = -8

x = -2

One Step Equations

100

Solve and verify. 14d = 154

d = 11

200

0.6x = 3.6

x = 6

300

x + 0.8 = 1.6

x = 0.8

400

209,668 = 989x

x = 212

500

(x / 525) = -643

x = -337,575

Multi-Step Equations

100

8x - 1 = 63

x = 8

200

-1 + 8a = 129

a = 16.25

300

-6 + (n/14) = -5

n = 14

400

6k + 3 = 125

k = 20.3333...

500

(d/12) + 25 = 29

d = 48

Mixed Equations

100

13 + 6n = 67

n = 9

200

A group of 9 friends takes a white-water rafting trip. The total price of the trip before any discounts is $810. Each person in the group receives a student discount. The total price with the discount is $729. How much is the discount per person?

The discount is $9 per person. (on a quiz or test I would want a complete sentence with units!)

300

You divide a stack of fliers for the Food Drive into 6 smaller stacks for volunteers to distribute. Each smaller stack contains 15 fliers. What is the total number of fliers distributed?

90 fliers are distributed. (complete sentence with units!)

400

An engineer receives a promotion that includes a raise of $4500 in her annual salary. Her new salary is $50,750. What was the engineer's salary before the promotion?

Before the promotion, her salary was $46,250. (complete sentence with units!)

500

Your family is taking a long-distance road trip. You begin with 16 gallons of gas in the tank. Your car uses 3 gallons of gas per hour of driving. YOu will need to stop for gas when there is 1 gallon left in the tank. After how many hours will you need to stop to refuel?

You will have to stop after 5 hours. (complete sentence with units!)

Word Problems

100

An online retailer charges $6.99 plus $0.55 per lb to ship electronics purchases. How many pounds is a DVD player for which the shipping charge is $11.94? Write an equation AND answer in a sentence.

6.99 + .55x = 11.94 It weighs 9 lbs.

200

Paulo has $145 in his savings account. He earns $36 per week mowing lawns. If Paulo saves all of his earnings, how many weeks will it take him to have $433? Write an equation and answer in a sentence.

145 + 36x = 433, It will take him 8 weeks.

300

Mrs. Jackson earned a $500 bonus for signing a one-year contract to work as a nurse. Her salary is $22 per hour. If her first week's check including the bonus is $1,204, how many hours did she work? Write an equation AND answer in a sentence.

500 + 22x = 1204, She worked 32 hours.

400

It costs $12 to attend a golf clinic with a local pro. Buckets of golf balls for practice during the clinic cost $3 each. How many buckets can you buy at the clinic if you have $30 to spend? Write an equation AND solve. Answer in a sentence

12 + 3x = 30, x = 6, You can buy 6 buckets of golf balls.

500

MOrgan subscribes to a website for processing her digital pictures. The subscription is $5.95 per month and 4 by 6 inch prints are $0.19 each. How many prints did Morgan purchase if the charge for January was $15.83? Write an equation AND answer in a sentence

5.95 + .19x = 15.83, She bought 52 prints.