Missing Variable in Equations

Solve the equation for the missing variable:

r + 20 = 27

• r = 7

• r = 13

• r = 47

• r = 20

Solve the equation for the missing variable:

s - 22 = 50

• s = 28

• s = 72

• s = 20

• s = 75

Solve the equation for the missing variable:

s + 18 = 24

• s = 42

• s = 18

• s = 9

• s = 6

Solve the equation for the missing variable:

y - 33 = 147

• y = 114

• y = 180

• y = 177

• Answer not given

Solve the equation for the missing variable:

17 = x + 3

• x = 20

• x = 13

• x = 14

• x = 19

Solve the equation for the missing variable:

x + 12 = 20

• x = 32

• x = 8

• x = 15

• x = 30

Solve the equation for the missing variable:

g - 15 = 30

• g = 35

• g = 15

• g = 45

• g = 12

In the equation x + 7 = 12, 7 is being added to the variable, x. How should you show your work to isolate the variable and solve the equation?

• Subtract 7 from both sides. The solution is x = 5

• Multiply both sides by 7. The solution is x = 84

• Add 7 to both sides. The solution is x = 19

• Subtract 12 from both sides. The solution is x = 9

What equation matches the situation? Jack had some markers, and then bought 6 more. Now he has a total of 10 markers.

• m - 6 = 10

• 10 - 6 = m

• m + 6 = 10

• Answer not given

x - 62 = 123

How should you show your work to isolate the variable and solve the equation?

• Add 123 to each side

• Subtract 62 from each side

• Multiply each side by 62

• Add 62 to each side