Question

choose 1 answer: (a) $x = \sqrt{53}$ (b) $x = \sqrt{45}$ (c) $x = \sqrt{14}$ (d) $x = 9$

Explanation:

Step1: Apply Pythagorean theorem

In a right - triangle, $a^{2}+b^{2}=c^{2}$, where $c$ is the hypotenuse. Here, $a = 7$, $b = 2$ and $c=x$. So $x^{2}=7^{2}+2^{2}$.

Step2: Calculate the right - hand side

$7^{2}+2^{2}=49 + 4=53$. Then $x=\sqrt{53}$ since $x>0$ (as it represents the length of a side of a triangle).

Answer:

A. $x = \sqrt{53}$