9x+13=2x+48
-2x -2x
7x+13=48
-13 -13
7x=35
/7 /7
x=5
y=9(5)+13
y=45+13
y=58
The number in the photo should be the answer but the problem might just be that your question was worded incorrectly.
if you don't have a Unit Circle yet, this is a good time to get one, you can find many online, check maybe in yahoo images, or google images.
Check the picture below.
notice the section encircled in purple.