Question

3(5n+8)=8(4+2n)
15n+24=32+16n
n=8
Describe the error.

Answer 1

n = -8

Explanation:

We need to work through the problem, to see how the individual got n = 8:

`3(5n+8)=8(4+2n)\\15n+24=32+16n\\15n=8+16n\\-n = 8\\n = -8`

It is clear that when the individual got to -n = 8, they forgot to divide by -n.

The - symbol simply represent -1 so to fully isolate n, we need to divide both sides by -1 to get n = -8.