Question 152051
Close but no cigar.

Given{{{-5+y=8}}}

What you want to do is get the y on one side of the equation by itself. That part you got right.

Think of an equal sign as if it is a balance point. Whatever you do to one side of the equation, you must do to the other side.

In this case, in order to get the y by itself, you need to 'get rid of" the (-5). 
If you add 5 to (-5), you get 0. But if you add 5 to the left side, you must then also add 5 to the right side.

{{{5 -5 + y = 5 + 8}}}
{{{0 + y = 13}}}
{{{y = 13}}}

Get it??

Always check your anwer using the original equation.
{{{-5+y=8}}}  substitute  13 for x
{{{-5 + 13 = 8}}} simplify
{{{8 = 8 }}} Which is true, so that value if x is correct