Respuesta :

Answer:

x = 15 ft

Explanation:

Given:

A right-angled triangle with two sides given

To find:

the measure of the third side

From the diagram:

hypotenuse = x ft

opposite = 12 ft

adjacent = 9 ft

To get the third side, we will apply Pythagoras theorem:

Hypotenuse² = opposite² + adjacent²

Substitute the values into the formula:

[tex]\begin{gathered} x^2\text{ = 12}^2\text{ + 9}^2 \\ x^2\text{ = 144 + 81} \\ x^2\text{ = 225} \\ x\text{ = 15} \end{gathered}[/tex]