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Tagged: Ratios, Similar Triangles

Find the value of x

$$\frac{x}{x-4}=\frac{9}{x}$$ cross multiply 7x = 9(x – 4) 7x = 9x – 36 -9x -9x

-2x = -36

x = 18

$$\frac{x}{12}=\frac{4}{10}$$ $$^{\cancel{12}\times}\frac{x}{\cancel{12}}=\frac{4}{10}\times12$$ x = 4.8cm

Find y in the pair of similar triangles

$$\frac{y}{16}=\frac{8}{12}$$ $$^{\cancel{16}\times}\frac{y}{\cancel{16}}=\frac{8}{12}\times16$$

y = 10^{2}/_{3}

$$\frac{x}{24}=\frac{12}{27}$$ $$^{\cancel{24}\times}\frac{x}{\cancel{24}}=\frac{12}{24}\times 27$$

x = 10^{2}/_{3}