Question

What value of c makes the trinomial below a perfect square?

4x2 + 16x + c

Answer 1

4x^2+16x+c
(2x)^2 + 2*2x*4 + (4)^2 = (2x+4)^2 = a perfect square so, (a+b)^2 = a^2+2ab+b^2)
in our case: a = 2x b = 4
c = 4^2 = 16