Find dy/dx.

Question

x = t^2, y = 4 − 2t

Answer 1

dy/dx = (dy/dt) / (dx/dt) = (-2)/(2t) = -1/t

check:
t = (4-y)/2
x = t^2 = (4-y)^2/4
dx/dy = -(4-y)/2
dy/dx = -2/(4-y) = -2/(4 - (4-2t)) = -2/(2t) = -1/t