Question

Twenty less than 8 times a number is the same as 15 more than the number.

Answer 1

X-number
8x-20=15+x (subtract x)
7x-20=15 (then add 20)
7x=35 (then divide by 7)

I think you've got it from now, if not, just do 35 divided by 7. But go over the steps, so that you know how to do these types of questions.

Answer 2

8x-20=15+x

x=number

Each side of the equation should be equal to each other