SOLUTION: y=x^2-4 5x+y=20 solve by the following system of substitution

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Question 955009: y=x^2-4
5x+y=20
solve by the following system of substitution
Answer by Fombitz(32388) About Me  (Show Source):
You can put this solution on YOUR website!
5x%2B%28x%5E2-4%29=20
x%5E2%2B5x-4=20
x%5E2%2B5x-24=0
%28x%2B8%29%28x-3%29=0
Two solutions:
x%2B8=0
x=-8
Then,
y=%28-8%29%5E2-4
y=64-4
y=60
and
x-3=0
x=3
Then,
y=%283%29%5E2-4
y=9-4
y=5
So the two solutions are (-8,60) and (3,5)