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What times what gives me -48 but adds to be -32?

User Spotman
by
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1 Answer

4 votes

Answer:

a couple of irrational numbers: -16±4√19, approximately {1.436, -33.436}

Explanation:

Your question can be cast as the quadratic equation

x² +32x -48 = 0

The solutions can be found using the quadratic formula:

x = (-32 ±√(32² -4(1)(-48)))/(2(1)) = -16±√304 = -16±4√19

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Comment on the equation we used

We notice that when p and q are roots, the equation can be written ...

(x -p)(x -q) = 0 = x² -(p+q)x +pq

You want p+q = -32, pq = -48, so the equation is ...

x² -(-32)x +(-48) = 0

x² +32x -48 = 0 . . . . . . with parentheses eliminated

User Kaolin Fire
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4.7k points