EXPLANATION:
To calculate the length of side x we must use one of the trigonometric functions.
We have the hypotenuse and the value of the opposite leg; now we must calculate the adjacent leg.
The exercise is as follows:
[tex]\begin{gathered} a=9 \\ b=6 \\ c=x \\ c=\sqrt[]{a^2-b^2} \\ c=\sqrt[]{(9)^2-(6)^2} \\ c=\sqrt[]{81-36} \\ c=\sqrt[]{45} \\ c=6.7 \\ \\ \text{the answer is x}=6.7 \end{gathered}[/tex]To check if it is ok we must replace the values and find the hypotenuse.
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