Step Equations Find Mistakes

4x + 7 = 23

• 4

• 7.5

• 64

• -4

A student solved this problem. What mistakes, if any, were made?

• On step 1, he added 4 to both sides. You cannot add the same number to both sides of an equation.

• On step 2, he moved the = sign. He should have 5m + 10 = 0 instead of 5m = 10.

• On step 3, he divided both sides by 5. He should have divided both sides by 5.

• There are no mistakes.

A student solved this problem. Find any mistakes if there are any.

• On step 2, the student eliminated the m's when they don't eliminate. -2m - 2m does not equal 0.

• On step 3, the student added 1 to get rid of the subtracted 1. He should have subtracted 1.

• On step 4, the student added 6 and 1 incorrectly.

• There are no mistakes in this problem.

What is the first step in solving this equation:
5x + 7 = 12

• Divide by 5

• Subtract 5

• Multiply by 7

• Subtract 7

What operation would you perform first and then second when solving for m in the following equation?
10 + 7m = 17

• subtract 10, divide by 7

• divide by 7, subtract 10

• multiply by 7, add 10

• add 10, multiply by 7

88 = 25 + x

• x = 113

• x = -113

• x = -63

• x = 63

• Infinite number of solutions

• (0, 7)

• (-5, -7)

• (5, 7)

Mackenzie is solving the system of equations using substitution. Her work is shown. What should be her next step?

• Nothing, she is done.

• Plug back into one of the equations to find x.

• Write her solution as an ordered pair

• She needs to check her work to make sure she made no mistakes.

Find the mistake in the problem shown in the image.

• Step 1: Need to add 1 instead of subtract 1.

• Step 2: Need to multiply by 3 instead of divide.

• This work has no mistakes.

Find the mistake in the work shown.

• Step 1: They distributed incorrectly.

• Step 2: They combined like terms incorrectly.

• Step 3: They combined unlike terms.

• Step 4: They divided instead of multiplying by 4.