SOLUTION: Find the points of intersection of x^2-4y=1 and x^2+x-2y=8

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Question 1018314: Find the points of intersection of x^2-4y=1 and x^2+x-2y=8
Answer by Fombitz(32388) About Me  (Show Source):
You can put this solution on YOUR website!
From eq. 2,
2y=x%5E2%2Bx-8
So then,
4y=2x%5E2%2B2x-16
Substitute into eq. 1,
x%5E2-%282x%5E2%2B2x-16%29=1
-x%5E2-2x%2B15=0
x%5E2%2B2x-15=0
%28x%2B5%29%28x-3%29=0
Two solutions:
x%2B5=0
x=-5
Then,
2y=%28-5%29%5E2-5-8
2y=25-13
2y=12
y=6
(5,6)
and
x-3=0
x=3
Then,
2y=9%2B3-8
2y=4
y=2
(3,2)
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