SOLUTION: Solve: y= 2x AND x^2 + y^2= 125 Full solution please I need help to understand!

Question 883018: Solve:
y= 2x
AND
x^2 + y^2= 125
Full solution please I need help to understand!
Answer by stanbon(75887) (Show Source): You can put this solution on YOUR website!
Solve:
y= 2x
AND
x^2 + y^2= 125
Full solution please I need help to understand!
=====================
Since y = 2x,
x^2 + (2x)^2 = 125
x^2 + 4x^2 = 125
5x^2 = 125
x^2 = 25
x = 5 or x = -5
----------------------
If x = 5, y = 2x = 10
If x = -5, y = 2x = -10
---------------------------
Cheers,
Stan H.
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