We begin by cross-multiplying: \(2x(x+4) = (x-5)(x+5)\)
We can expand both sides to get: \(2x^2+8x=x^2-25\)
We can move everything to the left-hand side, which gives us: \(x^2+8x+25=0\)
We now have to solve for x using the quadratic formula.
Can you do it?
Hint: The answer isn't real.