Variable Equations

18+m=38

• m=0

• m=10

• m=20

• m=8

What equation matches this situation?
Robyn had some video games then bought 4 more.  Now she has a total of 10 games.

• v - 4 = 10

• v + 4 = 10

• 10 - 4 = v

• Answer not Given

Amy was given an amount of money, m, for a good grades on her report card. She spent $15.00 and now has $25.32. How much money did she get for good grades? Write an equation you could use to solve this problem. Use m as your variable.

• m-25.32=15

• m/25.32

• m-15=25.32

• 15m=25.32

How many packages of diapers can you buy with $40 if one package costs $8? (What is the unknown and what would be the equation?)

• n= # of diapers; 8n = 40

• n= # of packages; 8n = 40

• n= # of packages; 8 - n = 40

• n= # of packages; 8/n = 40

Amy wants to buy soda AND pizza for her Halloween party. She has $45 to spend. One case of soda costs $4, and one pizza costs $8. Write an equation that could be used to find a valid combination for as many cases of soda, x, and pizzas, y, as she can afford.

• 8x + 4y = 45

• 4x - 8y = 45

• 12xy = 45

• 4x + 8y = 45

Felicia is buying shirts for her baseball team. She will pay $9.30 for each shirt plus a one-time fee of $25.50 for the design.

Which equation can be used to find y , the total cost to buy x shirts?

• y=9.3x+25.5

• y =25.5x+9.3

• y=9.3x-25.5

• y=25.5x-9.3

Which of these equations has a slope of 2 and a y-intercept of 3? (Careful)

• 2x + y = 3

• 2y = 4x + 6

• y = 3x + 2

• -2x + y = 6

Evaluate 2a + 4b 
if a = 10     and    b = 6

• 20

• 24

• 44

• 4

In 2010, a tree was 8 feet tall. In 2011 the tree was 14 feet tall. Which equation would be used to find how many feet the tree grew?

• f + 8 = 14

• f - 8 = 14

• f/8 = 14

• 8f=14

Evaluate 8a - b     if a = 10   and   b = 6

• 74

• 38

• 1000

• 9000