The region enclosed by the graphs of y = x^2 and y = 2x is the base of a solid. For the solid, each cross section perpendicular to the y-axis is a rectangle whose height is 3 times its base in the xy-plane. Which of the following expressions gives the volume of the solid?

Just use long division to write it out

First we solve your equation step-by-step.4.5  (8  −  x)  +  36  =102  −  2.5  (3  x  +  24)step 1: 4.5  (8  −  x)  +  36  =  102  −  2.5  (3  x  +  24)simplify: (show   the  steps)−4.5  x  +72  =−7.5  x  +  42step 2: add 7.5  x to both sides.  −4.5  x  +  72  +  7.5  x  =−7.5  x+  42  +  7.5  x  3  x  +  72  =  42step 3: subtract 72 from both sides.  3  x  +  72  −  72  =  42  −  723  x  =  −30step 4: divide both sides by 3.3  x  3=  −303  x=  −10so x = -10