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What two numbers multiplied together equal -420, but added together equal 1

User Joe Bane
by
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2 Answers

1 vote
x * y = -420
x + y = 1.....x = 1 - y

y(1 - y) = -420
-y^2 + y = -420
y^2 - y - 420 = 0
(y + 20)(y - 21) = 0

y + 20 = 0 x + y = 1
y = -20 x - 20 = 1
x = 21

y - 21 = 0 x + y = 1
y = 21 x + 21 = 1
x = -20

ur 2 numbers are 21 and -20

User David Ma
by
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4 votes
-21 x 20 multiplied together equal -420 but added together equals 1
User Sachihiro
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8.5k points