To solve/simplify this all you have to do is group like terms (the x^2's with each other, the x's with each other, and the normal numbers, -8)
14x^2-8+5x-6x^2+2x
group the x^2 (add 14x^2 to -6x^2)
8x^2-8+5x+2x
group the x's together (add 5x and 2x together)
8x^2+7x-8
Your answer will be d) 8x^2+7x-8
Since your probably solving for W, isolate W by adding the -3n to both sides and get W=5n now use a calculator and multiply 5 and Pi. To Get 15.7.
I used N for pi since I don’t have that symbol
You need to specify what needs to be solved so I just assumed W