What multiplies to be -290 and adds to be -7

Atemperature of 1.64◦f corresponds to answer in units of ◦c.

Gravel is being dumped from a conveyor belt at a rate of 25 ft3/min, and its coarseness is such that it forms a pile in the shape of a cone whose base diameter and height are always equal. how fast is the height of the pile increasing when the pile is 14 ft high? (round your answer to two decimal places.) ft/min

What adds to be the bottom number but also multiplies to be the top number with 8 on the bottom and 15 on top