What is the formula to work out the area of a parallelogram?

The variable z is directly proportional to x, and inversely proportional to y. when x is 4 and y is 13, z has the value 1.2307692307692. what is the value of z when x= 9, and y= 20

Find the equation of the trend line (line of best fit). show your work i'm using the points (34,76) (42,91)

If each bricks costs and he can only buy one brick how much will it cost him to get the material to put around the outside of his garden?