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If two numbers have: a sum of -7 and their product is -8, then what are the two numbers?

1 Answer

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A) x + y = -7
B) x * y = -8
B) y = -8/x
A) x -8/x = -7
A) x² -8 = -7x
A) x² +7x -8 = 0
Using quadratic formula
x = [-7 +-sq root (49 +4*1*8)] / 2*1
x = [-7 +- sq root (81)] / 2
x1 = (-7 + 9) /2 = 1
x2 = (-7 -9) / 2 = -16/2 = -8



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