Question

how to write x^2+y^2=4x in terms of x=something

Answer 1

There are TWO answers. It will take either Completing the Square or the Quadratic Formula.

Answer 2

You need to first put all the x-terms on one side and all the rest on the other side:

x^2 + y^2 = 4x
x^2 - 4x = -y^2
x(x-4) = -y^2

x = -y^2/(x-4)

Answer 3

@tkhunny how do ya do it with quadratic formula

Answer 4

@Rav that's not the way to roll, sorry :(

Answer 5

Just write it down.

x^2+y^2=4x

x^2 - 4x + y^2 = 0

\(x = \dfrac{4\pm\sqrt{(-4)^{2} - 4(1)(y^{2})}}{2}\) - Done

Answer 6

OP, thx mate