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Complex Proportions

In this video we will be learning how to solve complex proportions (variables on both sides) using cross-multiplication.

For Example:

\frac{x}{20}=\frac{(x+1)}{30}\leftarrow First we cross-multiply

30x=20(x+1)\leftarrow Then we distribute the 20 to the x and 1

30x-20x=20x +20-20x\leftarrow Subtract 20x from both sides to isolate x

\frac{10x}{10}=\frac{20}{10}\leftarrow Divide by 10 on both sides

x=2
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