what two number mutiply to -240 but add up to 8

ANSWERS

2021-01-13 21:04:30

Let us assume the two unknown numbers to be "x" and "y". Then xy = -240 x = - (240/y) And x + y = 8 Now let us put the value of x in the second equation. We get x + y = 8 -( 240/y) + y = 8 y^2 - 240 = 8y y^2 - 8y - 240 = 0 y^2 - 20y + 12y - 240 = 0 y(y - 20) + 12(y - 20) = 0 (y - 20) (y + 12) = 0 So we can see that the unknown number y can have two values and hence the unknown number will also have two values. When y - 20 = 0 y = 20 Then xy = - 240 20x = - 240 x = -12 So we can see that when y is equal to 20 then x is equal to -12 and when y is equal to -12 then x is equal to 20. So the two numbers are 20 and -12.

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