Question

I dont understand this

Answer 1

Answer: First option.

Explanation:

You need to remember the following Trigonometric Identity:

`cos\alpha =(adjacent)/(hypotenuse)`

In this case, you can identify in the figure that:

`\alpha =35\°\\adjacent=9\\hypotenuse=x`

Then you must substitute these values into
`cos\alpha =(adjacent)/(hypotenuse)`:

`cos(35\°) =(9)/(x)`

Finally, you need to solve for "x" in order to find its value. This is:

`(x)(cos(35\°))=9\\\\x=(9)/(cos(35\°))\\\\x=10.98`

Rounding the result to the nearest tenth, you get:

`x\approx11`