Melinda wants to paint the exterior lateral surface of her house. It is 9 feet high and has a perimeter of 140 feet. Each gallon of paint covers 300 square feet. How many one-gallon cans of paint does she need to buy to paint her house?

7x+8y=-18, 4x-9y=-3 solve the system of equations

You drop a rubber ball off the roof of a 50 meter high building onto a paved parking lot. it bounces back up with every bounce, but not quite all the way back up to you. after the first bounce it bounces back only 80 percent of the distance it was dropped from. the pattern continues, meaning after every bounce it comes up to just 80 percent of the previous maximum height. so if before the first bounce the height is 50 meters, what height does the ball reach after the fifth bounce? round your answer to one decimal place and chose the correct response from the choices below:

The general form of the quetion of a circle is ax^2+by^2+cx+dy+e=0 where a=b=0 if the circle has a radius of three units and the center lies on the y axis which set of values of a, b, c, d, and e might correspond to the circle