Super Math Question 3! Will tell Secret of Life Part 3 to whoever helps! Wanna know?

Question

Solve:
xy= -15
x+y = -2

Caution: there are more than one solution.
Note: Enable email so I can tell the Secret of Reality.

Answer 1

First, I'd rearrange the second equation to get: y = -2 -x

Plugging this into the first equation, we get:
x*(-2 - x) = -15
Getting rid of parentheses, this is:
-x^2 -2x = -15
Rearranging:
x^2 + 2x - 15 = 0

This factors neatly into (x+5)*(x-3) = 0
So the two possible x-values are:
x = -5 and x = 3

Since y = -2 - x,
when x = -5, y = 3
and when x = 3, y = -5.

Hence, the two answers are (-5, 3) and (3, -5).

Hope that helps!

Answer 2

Given:
xy= -15
x+y = -2

You find that x = -2-y from the second equation.

Plug this into the first.

You get (-2-y)y = -15
-y^2-2y = -15

Moving things around, you get

y^2+2y-15 = 0

Factor out to get (y+5)(y-3) = 0

Therefore, y = 3 or -5

Then plug it into the equation to get y.

If y=-5, x= 3
If y=3, x=-5

Answer 3

x equals negative 5, y equals 3. I don't see how there can be too many other solutions. And I already know the secret of reality. This is on the house.

Answer 4

y = -x - 2
substitute

x(-x - 2) = -15
-x2 -2x +15 = 0
(-x + 3) * (x + 5) = 0

x = 3 or -5

x = 3
y = -3 - 2 = -5

x = -5
y = -(-5) - 2 = 3

so solutions are:
x = 3, y = -5
x = -5, y = 3
.

Answer 5

x=-5
y=3