SOLUTION: Use elimination method to find all solutions of the systems of equations. 4x^2-y^2=75 x^2+5y^2=150

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Question 529564: Use elimination method to find all solutions of the systems of equations.
4x^2-y^2=75
x^2+5y^2=150
Answer by ankor@dixie-net.com(22740) About Me  (Show Source):
You can put this solution on YOUR website!
Use elimination method to find all solutions of the systems of equations.
4x^2 - y^2 = 75
x^2 + 5y^2 = 150
Multiply the 1st equation by 5, add to the 2nd equation
20x^2 - 5y^2 = 375
x^2 + 5y^2 = 150
--------------------adding eliminates y^2, find x
21x^2 = 525
x^2 = 525%2F21
x^2 = 25
x = +/-sqrt%2825%29
x = +5
x = -5
:
Find y
x^2 + 5y^2 = 150
25 + 5y^2 = 150
5y^2 = 150 - 25
5y^2 = 125
y^2 = 125%2F5
y^2 = 25
y = +/-sqrt%2825%29
y = +5
y = -5
:
You can check all 4 solutions in the original equations