Two-Step Equations

A cell phone company charges $3.00 to make a phone call plus $0.15 for each minute for each minute you talk. Which equation would you use to determine the total cost, c, of a phone call that is m number of minutes long?

• c = 3.00 - 0.15m
• c = 0.15 + 3.00m
• 3.00 = c + 0.15
• c = 3.00 + 0.15m

Samuel bought 3 tires for $79.95 each and some rims for $59 each. He spent a total of $534.85. Which equation could be used to find the number of rims, r, Samuel bought?

• 3(79.95) - 59r = 534.85
• 79.95r - 59(3) = 534.85
• 3(79.95) + 59r = 534.85
• 79.95r + 59(3) = 534.85

Julie bought 5 pairs of shoes and 4 blouses. The shoes were priced at $19 per pair and the blouses cost $16.50 each. Which equation can be used to find the total cost, t, she spent on the shoes and blouses?

• 5(16.50) + 4(19) = t
• 5(16.50) - 4(19) = t
• 4(16.50) + 5(19) = t
• 4(16.50) - 5(19) = t

Which equation matches the following situation? 331 students went on a field trip. Six buses were filled and 7 students traveled in cars. How many students were in each bus?

• n= # of students in each bus; 6n + 7 =331
• n=# of buses; 6n + 7 =331
• n= # of students in each bus; 6 + 7n =331
• n= # of students in each bus; 6n - 7 =331

WRITE AN EQUATION
April had $24 to spend on seven pencils. After buying them she had $10. How much did each pencil cost?

• n=total cost pencils; 7n+10=24
• n=cost of 1 pencil; 7n-10=24
• n=cost of 1 pencil; 7n+10=24
• n=cost of 1 pencil; -7n-10=24

Bonnie spent half of her weekly allowance playing mini-golf. To earn more money her parents let her wash the car for $4. What is her weekly allowance if she ended with $12?  (Define 'n' and write the equation.) 

• n=wkly allowance; 2n-4=12
• n=wkly allowance; 2n+4=12
• n=wkly allowance; n/2-4=12
• n=wkly allowance; n/2+4=12

Translate the sentence into an equation:
Four more than six times a number is 18.

• 10x = 18
• 4x + 6 = 18
• 4 + 6x = 18
• not enough info

You bought a magazine for $5 and four erasers. You spent a total of $25. How much did each eraser cost?  (Define 'n' and write the equation.) 

• n=total cost of erasers; 5 + 4n = 25
• n=cost of 1 eraser; 5 - 4n = 25
• n=cost of 1 eraser; 5n + 4 = 25
• n=cost of 1 eraser; 5 + 4n = 25

Sha' won 40 super bouncy balls playing horseshoes at her school's game night. Later, she gave two to each of her friends. She only has 8 remaining. How many friends does she have? (Define 'n' and write the equation.) 

• n=# of friends; 2n-8=40
• n=# of friends; 2+n+8=40
• n=# of friends; 2n+8=40
• n=# of friends; 2+8n=40

Which equation represents the total cost of a repair by an electrician after x hours?
An electrician charges $90 per hour plus a $50 travelling fee.

• y = 50 - 90x
• y = 90x + 50
• y = -50x + 90
• y = -90 - 50x