# maths

Need help to know what to do:

solve the equation
9/(x=7)=4/(x-3)

My book tells me to cross multiply, then move all the terms in x and the terms without x on separate sides of the equation. then divide by the coefficient of x. How do i do this?

I don't understnd it what that means.

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1. Cross multiple means:
nominator of left side x denominator of right side = nominator of right side x denominator of left side

So for this case:
9 * (x-3) = 4 * (x-7)
9x - 27 = 4x - 28

Now, let's collect the variable x on the left side, and the rest on the right side.
9x - 4x = 27 - 28
5x = -1

To find the final result, divide the right side with the coefficient of x.

x = -1/5

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