SOLUTION: what two numbers whose product is minus−72 and whose sum is 21. These numbers will be the constants in the binomial factors.

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Question 1060137: what two numbers whose product is minus−72 and whose sum is 21. These numbers will be the constants in the binomial factors.
Answer by math_helper(2461) About Me  (Show Source):
You can put this solution on YOUR website!
Let x = first number
y = 2nd number
xy+=+-72 (1)
x%2By+=+21 (2)
(1) —> +y+=+-72%2Fx+ (1a)
Substitute this into (2):
+x+%2B+%28-72%2Fx%29+=+21+
+x%5E2+-72+=+21x+ (multiplied both sides by 'x')
+x%5E2+-+21x+-+72+=+0+
+%28x%2B3%29%28x-24%29+=+0+
So +x=-3 or +x=24+
Using (1a):
+x=-3 —> +y=24+
+x=24 —> +y=-3 (the two answers just swap x & y, makes sense)
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Ans: The two numbers are -3 and 24
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Check:
-3*24 = -72 (ok)
-3+24 = 21 (ok)
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