Expressions and equations review

Simplify the following expression:
-10x + 15 - 3x + 2

• 13x² + 17
• -13x² + 13
• -13x + 17
• -7x + 17

Simplify the following expression:
-8x + 4x

• -12x
• -4x
• 4x
• 12x

Combine like terms
3x + 2x + 3y - 7y

• 5x + 10y
• 5x + 4y
• 5x - 4y
• 5x -10y

Simplify -5(x + 4)

• 5x + 4
• -5x + 4
• -5x - 20
• -5x + 20

Simplify.
-5n + 2(4 - 5n)

• -15n + 8
• -5n - 2
• -5n + 9
• 5n + 8

Solve the equation: 
x + 7 = 12

• x = 5
• x = 19
• x = -5
• x = 84

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.
• Add 7 to both sides.
  The solution is x = 19.
• Multiply both sides by 7 The solution is x = 84.

The variable, k, is being divided by 11. How should you show your work to isolate the variable?

• Divide both sides by 11
• Multiply both sides by 11.
• Add 11 to both sides.
• Subtract 11 to both sides.

What is the difference between an expression and equation?

• Expressions have an equal sign and equations do not have an equal sign
• Expressions do not have an equal sign and equations do have an equal sign
• There is not a difference
• Expressions do not have variables and equations have variables

What is the first step in solving the following equation?
3x - 5 = 20

• multiply both sides by 5
• add 5 to both sides
• divide both sides by 5
• subtract both sides by 5