The rectangular

The rectangular trapezoid has bases 15 dm and 8 dm long, and the length of the inclined arm is 12 dm. How long is the other arm of the trapezoid?

Correct answer:

d =  9.7468 dm

Step-by-step explanation:

$$\begin{gathered} a=15\text{dm} \\ c=8\text{dm} \\ b=12\text{dm} \\ x=a-c=15-8=7\text{dm} \\ {b}^2=x^2+d^2 \\ d=\sqrt{b^2-x^2}=\sqrt{12^2-7^2}=\sqrt{95}=9.7468\text{dm} \end{gathered}$$

Try another example