He maybe accidently added both of thm .
But if we difference we get 7.
Because - and - =+
So
-11+4=7.
Answer-44
You can turn both of the denominators ( bottom numbers on the fractions ) into 120 ( the whole number ) and the top numbers can be multiplied by how many times the denominators went into 120. Then add the top numbers which equals 76 and then 120-76=44. Hope that kinda helps !!
In slope intercept form this would just be: y=-3