Yes! These problems you would use Soh Cah Toa since these are right triangles. You will take the sine, cosine, or tangent of the angle given (not the 90 degree angle). You find out which one you need to use by looking at the other values given to you. Soh means that the sine of your given angle is equal to the length of opposite side from your given angle over (divided by) the hypotenuse. Cah means that the cosine of your angle equals the side adjacent to your given angle over (divided by) the hypotenuse. Toa means the tangent of your given angle is equal to the opposite side divided by the adjacent side.
I will do number 17 and then number 23 as examples.
17) First you will want to figure out what function (sin, cos, tan) you will be using. From the triangle, you can see that you will use sin because you are given 11 as your opposite side length and x as your hypotenuse. Using Soh Cah Toa, you are going to set up your equation.
sin(71)=11/x
Now you are going to solve for x like a normal equation. Multiply by x on both sides, and then divide both sides by the sin(71). You should be able to type this into your calculator and get an exact answer. I get approximately 11.6 for x.
23) This problem is very similar except this time you are solving for the angle, not a side length. You are given 10 for your adjacent side and 26 for your hypotenuse so you should use cosine (Cah). Set your equation up the same.
cos(x)=10/26
In order to solve this equation, you have to use the inverse of cos which is cos^-1. You should be able to type cos^-1(10/26) into your calculator (depending on the calculator you have) to get the approximately 67.4 degrees.
Bottom line: remember Soh Cah Toa!!!