Which expression can be used to find the sum of the polynomials? (9-3x^2)+(-8x^2+4x+5)

The square pyramid has a volume of 441 cubic inches. what is the value of x? 1/7x is the height x is the base

How do i simply this expression (quadratic formula basis) on a ti-84 or normal calculator?

Coleen made 1,000 bracelets to sell at a flea market. she sold each bracelet for $5.50. if she sold all of the bracelets, how much money did coleen make? $550 $5,500 $55,000 $550,000