Question

what is the length of the dotted line in the diagram below? round to the nearest tenth.

Explanation:

Step1: Identify right - triangle

The dotted line is the hypotenuse of a right - triangle with legs of lengths 7 and 10.

Step2: Apply Pythagorean theorem

The Pythagorean theorem is $c=\sqrt{a^{2}+b^{2}}$, where $a = 7$ and $b = 10$. So $c=\sqrt{7^{2}+10^{2}}=\sqrt{49 + 100}=\sqrt{149}$.

Step3: Calculate and round

$\sqrt{149}\approx12.2$.

Answer:

$12.2$