Two numbers that when added equal 90 and when multiplied equal -42?

Answer 1

48

Answer 2

The answer is 90.4627 and -0.4627.

The algebraic expression to get to the answer could be presented as follows:

X + Y = 90

X * Y = -42

Solving one equation for Y gives the following:

Y = -42 / X

Substituting for Y in the equation that we didn't use gives the following:

X + -42/X = 90

X - 90 = 42/X

(X-90)*X = 42

X*X - 90X = 42

Using iteration, we find that the value for X is 90.46427

Putting X back into one of the original equations, we get the following:

X + Y = 90

90.46427 + Y = 90

Y = -0.46427

So the solution set is:

X = 90.46427

Y = -0.46427