Answer:
47.5
Step-by-step explanation:
If r is parallel to s, then by the Alternate Exterior Angles Theorem:
x+56 = 3y-17. Additionally, (x+56)° is supplementary to (y+7)° because they make up a line.
So: 180 = x+56 + y+7 or
180-y-7 = x+56
Substitute into x+56 = 3y-17 so that 180-y-7 = 3y-17.
Solve for y to get y = 47.5
