Question

Part A: For what real values of c is x^2 + 16x + c the square of a binomial? If you find more than one, then list your values separated by commas.

Part B: For what real values of a is x^2 + ax + 25 the square of a binomial? If you find more than one, then list your values in increasing order, separated by commas.

Part C:For what real values of c is 9x^2 + 16x + c the square of a binomial? If you find more than one, then list your values in increasing order, separated by commas.


Thanks for helping!

Answer 1

(x+/-b)(x+/-b)
2 b = 16
b = 8
(x+8)(x+8)=x^2+16 x + 64

Answer 2

same deal,
(x-5)^2
or
(x+5)^2
a = 10 or -10

(9)(x^2+16/9 x + c/9)
9(x+8/9)(x+8/9)
(3x+8/3)(3x+8/3)
64/9