Multply both sides of the equation by 7.
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When the variable is in the numerator of a proportion like this, you can solve it by multiplying by that denominator. That multiplication cancels the denominator and gives you the value of the variable.
In general, you multiply by the reciprocal of the coefficient of x. When that coefficient is 1/7, you multiply by 7/1. Of course, you know that 7/7 = 1 and that x/1 = x.
There are two c's. You must pay attention to capitalization, there's a lowercase c and an uppercase C which represent two different variables. Also, the W is capitalized which could make your answer incorrect if you don't use the same notation.
Solving for small c..
So it's the answer shown in the picture, but it should be a capital W instead of a lowercase w.