Question

Fifteen less than twice a number is 53.solve 2n-15=53

Answer 1

2n-15=53
You need to get n by itself. To do that we need to simplify the left hand side of the equation. To do so, we move everything away from n. First add 15 to both sides to eliminate it on the left side. 
2n-15+15=53+15
2n=68
next divide by 2 to solve for n
2n/2=68/2
n=34

Answer 2

First add 15 to both sides:

2n = 68

Then divide each side by two.

n = 34