two questions in one.. what do i need to improve for this art and second question is in picture 1 below..

Use set buikder notation to represent the following set: {, -2, -1, 0}

Given f(x)=2x^2-8x+6 and g(x)=3x-1 find f(x) +g(x) a. 2x^2+5x+5 b.2x^2-11x+7 c. 2x^2-5x+5 d.2x^2-5x-5

Louis wants to carpet the rectangular floor of his basement.the basement has an area of 864 square feet.the width of the basement is 2/3 it's length. what is the length of louis's basement