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Find all values of p so that px^2 + 40x + 16 is a perfect square.

User JMPergar
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For a quadratic of the form px^2 + 40x + 16 to be a perfect square, it must be able to be written in the form (mx + n)^2 for some real numbers m and n.

Expanding (mx + n)^2 gives:

(mx + n)^2 = m^2x^2 + 2mnx + n^2

Comparing this to the given quadratic, we can see that:

m^2 = p

2mn = 40

n^2 = 16

Solving for m and n, we find that:

m = ±√p

n = ±4

Therefore, in order for the quadratic to be a perfect square, the square root of p must be rational, and the value of p must be one of the following:

p = 0, 1, 16

So the possible values of p that make the quadratic a perfect square are 0, 1, 16.

User Jaga
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