When given an algebraic expression involving subtraction why is it best to rewrite the expression using addition before identifying the terms?

Three cylinders have a volume of 2836 cm^3. cylinder a has a height of 900 cm. cylinder b has a height of 225 cm. cylinder c has a height of 100 cm. find the radius of each cylinder. use 3.14 as an approximate for π

Find the equation using the point (4,8)

Find the volume of the wedge cut from the first octant by the cylinder z=12-3y^2 and the plane x+y=2.