4x^2-4y^2=======

Question

4x^2-4y^2

cant solve this problem

Answer 1

If you are solving for x, and the equation is equal to zero, then you would add 4y^2 to both sides

4x^2 = 4y^2

Divide by four.

x^2 = y^2

at this point if you take the square root of both sides you lose half the solution to this problem. Because as it stands right now if y = 1 or -1  x can also be 1 or -1. But if you do take the square root. the equation will be:

x = y         and if    y = 1     x must be equal to 1 also. the second solution is no longer present.

for most cases this is acceptable but not if you are graphing the full solution.