Usually, when calculating trigonometry, we have to use a calculator for this.
The way to enter this in the calculator is basically first pressing the button for "sin". Next, your screen should have " sin( " shown. now enter 33. When your calculator has "sin(33)" appeared, click "=" or "exe" whatever your calculator shows the answer for.
You should have 0.544639... Now, the way solve x, one trick I use is that if the unknown is the denominator, simply divide the numerator by the answer we just calculated. So, you can enter " 7 ÷ Ans " to your cal.
Now, the result should be 12.852549... And round this up to the tenth, your final answer should be 12.9