It looks like you have
[tex]20.5=\dfrac{w}{60^2}\cdot 703[/tex]
Then the coefficient of w is 703/3600. Multiply the equation by the reciprocal of that and you will have your answer.
[tex]20.5\cdot \dfrac{3600}{703}=\dfrac{w}{60^2}\cdot 703\cdot \dfrac{3600}{703}\\\\ \dfrac{73800}{703}=w\dfrac{3600}{60^2}\cdot \dfrac{703}{703}=w\\\\ 104.979\approx w[/tex]
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If the variable of interest is found in one term of the equation, and there are no other terms on that side of the equation, you can find the value of the variable by multiplying the equation by the inverse (reciprocal) of the variable's coefficient.
