How do you find the value of c that makes $x^2-15x+c$ into a perfect square?

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Answer 1 · 2016-12-23T01:19:02

$c = 225/4$

By the property $(a + c)^2 = a^2 + 2ac + c^2$ , we can solve for $c$ .

$2ac = -15$

$2(1)(c) = -15$

$c = -15/2$

The value of $c$ needs to be a perfect square, so $c= (-15/2)^2 = 225/4$ .

Hopefully this helps!

How do you find the value of c that makes x^2-15x+cx^2-15x+c into a perfect square?