12
28.
Find the sum: 1.3 +2.4 +3.5+ ... to n terms. 2

Find the sum of 4x^{2} -4+6 and -7^{2} +3x+1

Aconstruction worker needs to put a rectangular window in the side of a building he knows from measuring that the top and bottom of the window have a width of 8bfeet and the sides have a length of 15 feet he also measured one diagonal to be 17 feet what is the length of the other diagonal

If f(x)=x^2- 4 and g(x)=x^2 plus 2 x, (c) (f-/3) = ? (simplify your answer.)