Question

Which side lengths form a right triangle? Choose all answers that apply: A 3,4,5 7,8,9 3,9, 95

Answer 1

To know which forms a triangle, we have to use Pythagorean's Theorem.

$\begin{gathered} 5^2=3^2+4^2 \\ 25=9+16 \\ 25=25 \end{gathered}$

Option A forms a right triangle.

$\begin{gathered} 9^2=7^2+8^2 \\ 81=49+64 \\ 81=113 \end{gathered}$

Option B doesn't form a right triangle.

$\begin{gathered} (\sqrt[]{95})^2=9^2+3^2 \\ 95=81+9 \\ 95=90 \end{gathered}$

Option C doesn't form a right triangle.

Hence, the answer is A.