Solving for volume of a solid by integration. Two zeroes don't seem to be right. Guidance would be very helpful!

The base of a solid is the region in the ry-plane bounded by the curves y = 3 - -1- and y = 0. Every cross- section of the solid parallel to the z-axis is a triangle whose height and base are equal. ( f(x ) - 9 ( x ) ) 2 2 NJ- (3 - : $ 2 - 0 + d x (-3 x2 +3) ( * 2 + 3) ax 9 4 4 NH 2 + 9 )*x NI x ( 4 - x 2) X E - 2 a2 1- 7 (-2 ) ( 4 - (-2)2 0 N J- - (2 ) ( 4- (2 )27