Provided:

$\displaystyle y = 5 - x$

$\displaystyle x = (1/6)(y-5)^2$

How do I know to solve in terms of y or x?

So far I've tried it in terms of y and found the points of intersection to be -1, 5.. I tried evaluating the integral of $\displaystyle \int(5-y)-(1/6(y-5)^2)$, with the limits -1 to 5, but was marked incorrect... Any suggestions? Should it be in terms of x ?

Thanks,

John