Question

Michael solved the system of linear equations and provided the solution.

3x – 3y = 6
4x – 7y = 2

Step 1 4(3x – 3y = 6)
–3(4x – 7y = 2)
Step 2 12x – 12y = 24
–12x + 21y = –6
Step 3 9y = 18
Step 4 y equals 1 over 2


In which step did Michael show his first error? (2 points)

Step 2

Step 3

Step 4

No errors are present in the solution

Answer 1

Michael made his first error in Step 2. In that step, he incorrectly distributed the -3 when multiplying it with the second equation. It should be -3(4x - 7y) = -6, but he mistakenly wrote -12x + 21y = -6. This is where the error occurred in his solution.