Solving $\sin(\arcsin(a-x) -c) = \sin(\arcsin(b+x)+\pi-c) + d$ for $x$

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Find $x$ in terms of the constants: $a$, $b$, $c$, and $d$. $$\sin(\arcsin(a-x) -c) = \sin(\arcsin(b+x)+\pi-c) + d$$

(Assume $d$ is around $.01$-$.21$.)

I don't how to solve this problem or if it is even possible to solve. Please, help me solve it or show me why it is an impossible math question.

Thanks

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Use the identity $\sin(x+y) = \sin x\cos y+\cos x\sin y$ to expand the equation,

$$\sin[\arcsin(a-x) -c] = \sin[\arcsin(b+x)+\pi-c] + d$$

to

$$(a-x)\cos c-\sqrt{1-(a-x)^2}\sin c = -(b+x)\cos c+\sqrt{1-(b+x)^2}\sin c + d$$

where $\cos (\arcsin t) = \sqrt{1-t^2}$ is used. Rearrange the resulting equation to obtain the following,

$$\sqrt{1-(a-x)^2} = r-\sqrt{1-(b+x)^2}$$

where

$$r = \frac{(a+b)\cos c-d}{\sin c}$$

Then, square both sides (twice) to remove square-roots and you end up with a standard quadratic equation in $x$.