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What number multiplies to -5 and adds up to 6

User Stopshinal
by
4.4k points

1 Answer

1 vote

Answer:

The two numbers are
3-√(14) and
3+√(14).

Explanation:

I am assuming you meant "numbers", otherwise you question has no answer.

Let us call the two numbers
a and
b, then we have

(1).
ab =-5 (they multiply to -5)

(2).
a+b =6 (they add to 6}

We solve for
a and
b, by first solving for
a in equation (1):


a = -(5)/(b)

and substituting this value into equation (2):


-(5)/(b)+ b =6

multiply both sides by
b and rearrange to get:


-5+b^2 =6b


b^2-6b-5=0

Using the quadratic formula we solve for
b to get:


b = 3+ √(14)


b =3-√(14)

which when put into equation (1) give


a = 3-√(14)


a = 3+√(14).

Thus, the two numbers are
3-√(14) and
3+√(14).

User Mariowise
by
4.3k points