I'm having problems rearranging this formula to solve for c, could someone lend a hand please. It's a physics formula for projectile motion.
dy = 0.5*acc * (dx / (c*speed))^2 + (sqrt(1-c^2)*speed) * (dx/c*speed))
so far I have:
(dy*(c^2)) - (sqrt(1-(c^2))*dx*c) = (0.5*acc*(dx^2)) / speed^2
When you have an equation with some polynomial of $c$ added to the square root of some other polynomial of $c$ (here, the latter is proportional to $\sqrt{1-c^2}$ then you can solve for $c$ by moving the square root alone to the right side of the equality and getting the other terms all on the left, then squaring. In this case that gives you a quadratic equation in $c$ to solve, which is easy enough.
But if you also note that $\frac{dy}{dy}$ is the speed, then in fact the quadratic terms cancel and you can solve a linear equation for $c$.