Question

The work of a student to solve a set of equations is shown:

Equation 1: m = 8 + 2n
Equation 2: 6m = 4 + 4n


Step 1: −6(m) = −6(8 + 2n) [Equation 1 is multiplied by −6.]
6m = 4 + 4n [Equation 2]
Step 2: −6m = −48 − 12n [Equation 1 in Step 1 is simplified.]
6m = 4 + 4n [Equation 2]
Step 3: −6m + 6m = −48 − 12n + 4n [Equations in Step 2 are added.]
Step 4: 0 = −48 − 8n
Step 5: n = −6


In which step did the student first make an error?

A) step 3
B) step 5
C) step 4
D) step 2

Answer 1

You should isolate the steps and evaluate them. That is going to be the easiest way to see where things went wrong.