Multi Step Equations

2x + 3(5x - 7) = 47

• 1

• 2

• 3

• 4

-8(-8x - 6) = -6x - 22

• 2/5

• -1

• 8/7 

• 2

Find the Error
What error did the student make when solving the equation:
1/5x + 6 = 3/5x + 5
1x + 6 = 3x + 5
-2x + 6 = 5
-2x = -1
x = 1/2

• The student found an incorrect common denominator

• The student did not multiply all terms by the common denominator

• The student did not use opposite operations appropriately

• The student did not correctly eliminate the variable from one side of the equation

Find the Error
What error did the student make when solving the equation:
5x + 6 =  66
5x - 6 = 66 -6
5x = 60
5*5x= 60*5
x = 300

• The student subtracted 6 from both sides instead of adding

• Student multiplied by 5 instead of dividing by 5

• Student got the wrong answer when subtracting 66-6

• The student did not correctly eliminate the variable from one side of the equation

-(n - 8) = -2

• 6

• 10

• -10

• -6

Solve

• 5

• 2

• No Solution

• Infinitely Many Solutions

Find the error in the problem below
19 - 2k = 3k - 1
     +3k   +3k
19 + 1k = -1
-19           -19
k = -20

• They should have divided by 1 for the last step

• They should add 19 instead of subtracting 19

• I can not find an error

• Instead of adding 3k they should subtract 3k

How many solutions does the equation below have?
6(3a +1) - 30 = 3(2a - 4)

• Identity

• No Solution

• Three Solutions

• One Solution

Solve

• 2

• -8

• No Solution

• Infinitely Many Solutions

Solve: 10x + 9 = 4x - 9

• 3

• 0

• -18

• -3