Question

What mistake did this student make?

1. The 2nd equation should have been added to the 1st equation, not subtracted

2. The 2nd equation should have been multiplied by 3

3. The 1st equation should have been multiplied by 2

4. Neither equation is in standard form

Answer 1

The answer is 3) the 1st equation should have been multiplied by 2

Answer 2

3. the 1st equation should have been multiplied by 3