Question

I need a simple but deep explanation on how to solve this

Answer 1

Let x be the missing side. Since we have a right triangle, we can apply Pythagorean theorem:

$x^2+8^2=10^2$

Remember that the hypotenuse (10 in our case) is always in front of the right angle. Then, from the last result, we have

$x^2+64=100$

By subtracting 64 to both sides, we get

$x^2=36$

then x is given by

$\begin{gathered} x=\sqrt[]{36} \\ x=6 \end{gathered}$

Therefore, the answer is: 6