Solving 2p^2+8p=-3 using completing the square method?

The volume of gas a balloon can hold varies directly as the cube of its radius. imagine a balloon with a radius of 3 inches can hold 81 cubic inches of gas. how many cubic inches of gas must be released to reduce the radius down to 2 inches?

Find the area of the triangle shown 3 by 6

Aquadratic equation in standard from is written ax^2= bx+c, where a, b and c are real numbers and a is not zero?