Hello, qbkr21!

Find the value of if and

Here is what I did.

Now I drew a right triangle and labeled the angle with respect to

So the hypotenese was 17 and was 15.

Now to find the side of the triangle I applied Pythagorus' theorem

and set it up like this: . solved for←here!

According to me, cosine should be , but the computer won't accept the answer.

You overlooked one of the conditions: .

. . If is negative, then is in Quadrant 2 or 3.

Since is positive, is in Quadrant 1 or 2.

. . Hence, is in Quadrant 2.

Your triangle should look like this:Code:* | | \ 17 | 8| \ | | \ θ - + - - - + - - b |

Be very careful when using Pythagorus . . .

You had: .

. . Then: .±

And you must choose the correct sign, you see.