Parameters: 36691

Calculate the length of the arms and the area of the isosceles trapezoid if you know the following parameters:
o = 20 cm
a = 10 cm, c = 4 cm
h = 2 cm

Correct answer:

r =  3 cm
S =  14 cm²

Step-by-step explanation:

$$\begin{gathered} o=20\text{cm} \\ a=10\text{cm} \\ c=4\text{cm} \\ v=2\text{cm} \\ o=a+c+2\cdot r \\ r=(o-a-c)/2=(20-10-4)/2=3\text{cm} \end{gathered}$$

$S=\frac{a+c}{2}\cdot v=\frac{10+4}{2}\cdot 2=14{\text{cm}}^2$

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