Given a right-angled triangle
Where
[tex]\begin{gathered} \text{Hyp}=\text{Hypotenuse}=9\text{ units} \\ \text{Adj}=\text{Adjacent}=2\text{ units} \\ \text{Opp}=\text{Opposite}=x\text{ units} \end{gathered}[/tex]
The value of x can be deduced by using the Pythagorean theorem
The formula of the Pythagorean theorem is
[tex]\text{Hyp}^2=\text{Opp}^2+\text{Adj}^2[/tex][tex]9^2=x^2+2^2[/tex]
Solve for x
[tex]\begin{gathered} 9^2=x^2+2^2 \\ 81=x^2+4 \\ \text{Collect like terms} \\ x^2=81-4 \\ x^2=77 \\ \text{Square of both sides} \\ \sqrt[]{x^2}=\sqrt[]{77}^{} \\ x=\sqrt[]{77}\text{ units} \end{gathered}[/tex]
Hence, the answer is option B
