Solving a Physics Problem: Struggling with Algebra

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The discussion revolves around solving a physics problem that involves algebraic manipulation of an equation. The original equation is transformed by substituting constants with letters for simplicity, leading to a new equation format. To eliminate fractions, the participants suggest multiplying by the common factor, resulting in a quadratic equation. The next steps involve expanding the equation, rearranging it to standard form, and applying the quadratic formula to find the solution for X. This method streamlines the problem-solving process and clarifies the algebraic steps needed to arrive at the answer.
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Homework Statement



Ok this was a physics problem...

I'm having a hard time with the algebra part

Homework Equations



solve for X

7.35E22/(3.84403E8 - X)^2 = 5.98E24/X^2

The Attempt at a Solution



i have got down to this and I think it is right but it might be wrong

0 = (7.35E22 X^2)/5.98E24 - X^2 + 2(3.84403E8)X - (3.84403E8)^2
 
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Rather than dealing with all those long and annoying numbers, let's assign letters to stand for them, and we can substitute back after all the algebra is done.

Let:
A=7.35x10^{22}
B=3.84403x10^8
C=5.98x10^{24}

So now we have \frac{A}{(B-X)^2}=\frac{C}{X^2}

You want to get rid of the fractions, so you need to multiply by the higher common factor, which is X^2(B-X)^2

Then you'll get AX^2=C(B-X)^2

Now you need to expand, move everything to one side and let the equation = 0 and collect like terms. You should get it in the form mx^2+nx+p=0 where m, n and p are all some constant, and x is the variable that you're trying to solve.

Now you can apply the quadratic formula.
 
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