SOLUTION: hello I need help doing this system since I keep getting the wrong answer... thank you in advance! xy-x^2=-20 x-2y=3

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Question 677531: hello I need help doing this system since I keep getting the wrong answer... thank you in advance!
xy-x^2=-20
x-2y=3
Found 2 solutions by Alan3354, edjones:
Answer by Alan3354(69443) (Show Source):
You can put this solution on YOUR website!
xy-x^2=-20
x-2y=3 --> y = (x-3)/2
---------
xy-x^2=-20
Sub for y

(x+8)*(x-5) = 0
x = -8, y = -5.5
x = 5, y = 1

Answer by edjones(8007) (Show Source):
You can put this solution on YOUR website!
xy-x^2=-20
x-2y=3
.
x=2y+3
y(2y+3)-(2y+3)^2=-20
2y^2+3y-(4y^2+12y+9)=...
2y^2+3y-4y^2-12y-9=...
-2y^2-9y-9=-20
2y^2+9y+9=20
2y^2+9y-11=0
y=1, x=5
y=-11/2, x=-8
See below
.
Ed
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Solved by pluggable solver: SOLVE quadratic equation with variable

Quadratic equation (in our case ) has the following solutons:

For these solutions to exist, the discriminant should not be a negative number.

First, we need to compute the discriminant : .

Discriminant d=169 is greater than zero. That means that there are two solutions: .

Quadratic expression can be factored:

Again, the answer is: 1, -5.5. Here's your graph: