Drainage channel

The drainage channel's cross-section is an isosceles trapezoid whose bases are 1.80 m and 0.90 m long, and the arm is 0.60 meters long. Calculate the channel's depth.

Final Answer:

h =  0.4 m

Step-by-step explanation:

$$\begin{gathered} a=1.8\text{m} \\ c=0.9\text{m} \\ r=0.60\text{m} \\ x=\frac{a-c}{2}=\frac{1.8-0.9}{2}=\frac{9}{20}=0.45\text{m} \\ {r}^2=h^2+x^2 \\ h=\sqrt{r^2-x^2}=\sqrt{0.6^2-0.45^2}=0.4\text{m} \end{gathered}$$

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