Answer:
c = -5 and d = 1
Explanation:
First, multiply out (cy^2)(4y^d). We get: 4cy^(2+d).
We equate this result to the right side of the equation: - 20y^3.
Then, equating the exponents and solving for d, we get: 2 + d = 3, or d = 1.
Equating the coefficients, we get 4c = -20, or c = -5.