Solve the equation by completing the square.
7t2 + 28t + 56 = 0
t=
and t=

The size of a certain cell is 2.5*10^-9m. another cell is 1.5*10^3 times larger. how large is the larger cell in scientific notation?

Henry is an avid reader, he devours 90 pages in half an hour how many pages has henry read per minute?

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?