Explanation.
We are required to use the Pythagorean theorem
The Pythagoras theorem states that in a right-angled triangle, the square of the hypotenuse is equal to the sum of the squares of the other two sides.
According to this theorem,
From the given question, we have the hypotenuse and the legs shown below
So we will have our equation as
[tex]\begin{gathered} x^2+6^2=9^2 \\ \end{gathered}[/tex]
For the second part, if we make x the subject of the formula:
[tex]\begin{gathered} x^2+36=81 \\ x^2=81-36 \\ x^2=45 \\ x=\sqrt{45} \\ x=3\sqrt{5} \\ x=6.71 \end{gathered}[/tex]
Therefore, the value of x is 6.71
