Answer:
X=18.88
Explanation:
This is a 90 degree triangle which means that you can use Sin, Cos, Or Tan. In this case you have to use Tan as you don't know the hypotenuse length. Which means you would set up an equation that looks like Tan(42°)=17/x as tangent is opposite over adjacent. Then if you were to solve for X eventually you'll get X= 17/Tan(42°) and if you plug it in a calculator you would get that X= 18.88 or 19 if you round to a whole number.