What should be added to x2 +xy+y2 to obtain 3x2 - 4xy - y2​

The average of 5 distinct scores has the same value as the median of the 5 scores. the sum of the 5 scores is 420. what is the sum of the 4 scores that are not the median? * explain how you found the answer * a) 315 b) 320 c) 336 d) 350 e) 360

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 interior angles formed by the side of a hexagon have measures of them up to 720° what is the measure of angle a