What is the product of 2x + y and 5x – y + 3?

Find the value of tan theta if sin theta = 12/13 and theta is in quadrant 2

An an average person has 6×10 by the power of two as many red blood cells as white blood cells a small sample of the blood has 7×10 by the power of three white blood cells about how many red blood cells are in the sample

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