Question 103

Given that ∠ABC = 90°, BC is parallel to DE. If AB = 12, BD = 6 and BC = 10, then the length of DE is

Solution

BC | | DE

=> $$\angle$$ABC = $$\angle$$ADE = 90

and $$\angle$$ACB = $$\angle$$AED

$$\therefore$$ $$\triangle$$ABC $$\sim$$ $$\triangle$$ADE

=> $$\frac{AB}{AD} = \frac{BC}{DE}$$

=> $$\frac{12}{18} = \frac{10}{DE}$$

=> $$DE = 15$$ cm

Create a FREE account and get: