Solving One Step Equations

Solve: 2a - 4(a - 5) = 10

• 5

• 10

• 2

• -5

Solve: 3n - 4 = -2 +2n

• -4

• -2

• 6

• 2

• x = 1

• x = 2

• x = 3

• x = 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.

• x = 3

• x = 4

• x = 5

• no solution

• x = 8

• x = 9

• x = -1

• x = 2

A student solved this problem. Which, if any, describe the mistake(s) made?

• He distributed incorrectly on step 1. 6(x + 2) = 6x + 8

• He added 3x twice to the left side and added nothing to the right side. He made the scale unbalanced.

• On step 4, he should have added 12 to get rid of an added 12.

• There are no mistakes

• x = 2

• x = -5

• x = 1

• x = 3

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.

• x = 1

• x =2

• x = 3 

• no solution