SOLUTION: Find the value of c that makes x^2+5x+c a perfect square trinomial. Thanks for the help

Algebra ->  Quadratic Equations and Parabolas -> SOLUTION: Find the value of c that makes x^2+5x+c a perfect square trinomial. Thanks for the help      Log On


   

Question 41894: Find the value of c that makes x^2+5x+c a perfect square trinomial.
Thanks for the help
Answer by psbhowmick(878) About Me  (Show Source):
You can put this solution on YOUR website!
x%5E2%2B5x%2Bc
= %28x%5E2%2B2%2Ax%2A%285%2F2%29%2B%285%2F2%29%5E2%29%2Bc-%285%2F2%29%5E2
= %28x%2B5%2F2%29%5E2%2B%28c-25%2F4%29

As the first part is a perfect square so the second part must be definitely be zero.
So, c-25%2F4=0
or c = 25%2F4