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Besides of knowing the ratio of two sides is in proportion, I don't know how to go further.

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Em.
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Estudiantekriss
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1 Answers1

4

Since the sides with arrows are pairwise parallel, we know $\frac{6a}{b}=\frac{8b}{3a}$.

Then cross multiply, we get $18a^2=8b^2$.

$\Rightarrow \frac{a^2}{b^2}=\frac{8}{18}=\frac{4}{9}$

$\Rightarrow \frac{a}{b}=\frac{2}{3}$ (since $a>0$ and $b>0$)

So, $a:b=2:3$

David
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