Question 889697
Treat as a quadratic equation in the variable, x.  Use the general solution and substitute the given values for y and z.


{{{x^2+4xz-y^2=0}}}
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{{{x=(-4z+- sqrt(16z^2+4*y^2))/(2)}}}
{{{x=(-4z+- 2sqrt(4z^2+y^2))/2}}}
{{{highlight(x=-2z+- sqrt(4z^2+y^2))}}}.