Solving Equations and Justifying Steps

Solve.  5n - 4 = 21

• 10
• -5
• 5
• 2

Solve:
3(x - 2) = 18

• 6.7
• 4
• 8
• -4

6x + 3(-x + 11) = 3

• -10
• 10
• 15
• -15

• A
• B
• C
• D

0.75 + 2(a - 0.5) = 3a - 0.4

• 0.15
• 5
• 1.5
• 3.75

Which step cannot be performed first when solving the equation
5 - 2(x - 7) = x + 1 + 3x

• Distributing -2 to (x - 7)
• Combining x and 3x
• Subtracting 1 from both sides
• 5 - 2

Solve:

5y + 34 = -2(-7y + 1)

• y = -4

• y = 9

• y = 4

• y = 36/19

• No Solution

• Infinitely Many Solutions