Since these two have the same power and variable, you can just subtract right away. It’s going to be 7x^1/5
R(t) = 4t
A(r) = π(r^2)
a) A(t) = A[r(t)] = π[r(t)]^2 = π[4t]^2 = 16π(t^2)
b) t = 4,
A(4) = 16*3.14*(16)^2 = 12,861.44
The Y intercept is (0,275) and the X intercept is (125,0). the intercepts should be the point of when the line hits the axis'