Question

Does anyone knows how to solve this question??

Answer 1

24

Explanation:

From the mnemonic SOHCAHTOA you would know that cos x = adjacent/hypotenuse.

Adjacent side is given as 12, but we must calculate the hypotenuse.

For that we use Pythagoras.

hypotenuse = √(9²+12²) = 15

Now you can calculate

30×cos(x) = 30×12/15 = 24

Answer 2

24

Explanation:

cos(x) is just a trigonometric function. To find it on a right triangle, you take the "adjacent" side, which should be the side next to the angle x, and divide it by the hypotenuse.

In this case, the adjacent side is 12. We don't know the hypotenuse, but we can figure it out using the Pythagorean Theorem:
`\sqrt{9^(2)+12^(2)}` =
`√(225)` = 15. So, the hypotenuse is 15.

Thus, cos(x) = 12/15 = 4/5. We want 30 * cos(x), so we get: 30 * (4/5) = 24, and that is our answer.