SOLUTION: 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.

Algebra ->  Quadratic Equations and Parabolas -> SOLUTION: 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.      Log On


   



Question 1085953: 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.
Found 2 solutions by Boreal, MathLover1:
Answer by Boreal(15235) About Me  (Show Source):
You can put this solution on YOUR website!
take half of 16 and square it, so c=64
x^2+16x+64 is (x+8)^2. (8, 8) multiplicity of roots.
the vertex of this quadratic is at -b/2a for x, or x=-16/2=-8. y=-64+128, and c must be 64.

Answer by MathLover1(20849) About Me  (Show Source):
You can put this solution on YOUR website!

For what real values of c is x%5E2+%2B+16x+%2B+c the square of a binomial?
recall the square of a binomial:%28a%2Bb%29%5E2=a%5E2%2B2ab%2Bb%5E2
you have x%5E2+%2B+16x+%2B+c-> a=1, 2ab=16, and b%5E2=c
find b-> b=16%2F2a-> b=16%2F%282%2A1%29-> b=8
then, 8%5E2=c->c=64
x%5E2+%2B+16x+%2B+64
x%5E2+%2B+16x+%2B+8%5E2
%28x+%2B+8%29%5E2