Question 748794
Solve the given nonlinear system by the addition method.
4x^2 – 2y^2= –2
 x^2 + 4y^2 = 40 
:
Multiply the 1st equation by 2, add to the 2nd equation
8x^2 – 4y^2= –4
 x^2 + 4y^2 = 40
--------------------Addition eliminates y^2, find x^2
9x^2 = 36
divide both sides by 9
x^2 = 4
x = +/-{{{sqrt(4)}}}
x = +2, 
x = -2
:
Find y using the 2nd equation, we know x^2 = 4
4 + 4y^2 = 40
4y^2 = 40 - 4
4y^2 = 36
divide both sides by 4
y^2 = 9
y = +/-{{{sqrt(9)}}}
y = +3
y = -3 

:
Check our solutions in the 1st equation
4(4) - 2(9) = -2