I believe y=x+2 and y=-x+3 are perpendicular lines.
We know that
the Volume of a prism=a*b*c
a----> tall--------> 8 1/2 in=8.5 in
b-----> wide-----> 7 in
c-----> <span>thick-----> 2 1/2 in=2.5 in
therefore
V=8.5*7*2.5=148.75 in</span>³------------equal a 148 3/4 in³
the answer is the option <span>c 148 3/4 in³</span>
B, I believe. But go with your gut instinct
or 
The hypotenuse is the longest side of the triangle. The opposite is the side that is across from a point/angle. The adjacent is the side next to a point/angle.
At ∅ (pretend that's theta LOL), 17 is the hypotenuse, 8 is the opposite side, and 15 is the adjacent side.
So:
sin ∅ = Opposite/Hypotenuse
sin ∅ = 
cos ∅ = Adjacent/Hypotenuse
cos ∅ = 
tan ∅ = Opposite/Adjacent
tan ∅ = 