Question

If a+b=-3, ab=-10 find a and b.

Answer 1

Answer:

a+b = -3

a = -3 -b

ab = -10

(-3-b)b = -10

-3b - b^2 = -10

b^2 + 3b -10 = 0

b^2 + 5b - 2b - 10 = 0

b(b + 5) -2(b + 5) = 0

(b-2)(b+5)=0

b = 2 or -5

When b = 2 , a = -5

When b = -5, a = 2