Question

Nia solved the equation -1.98 = 5.2v + 13.1. Her answer was v = -2.9. She is fairly confident about her answer, but wants to do a quick check of her solution using estimation to make sure her answer is reasonable.

Which of the following shows a good check of her answer?

Answer 1

substitute for v, when v = -2.9

Explanation:

`-1.98=5.2v+13.1`

subtract 13.1 on both sides.

`-15.08=5.2v`

divide by 5.2 to isolate v

`(-15.08)/(5.2) = (5.2v)/(5.2)`

`-2.9=v`

substitute for v

`-1.98=5.2(-2.9)+13.1`

`-1.98=-15.08+13.1`

`-1.98=-1.98`