Explain what the following statement means: Polynomials are closed under the operations of
addition and subtraction.
Provide one addition example and one subtraction
examnle to demonstrate

Aball is thrown from a height of 139 feet with an initial downward velocity of 15 ft/s. the ball's height h (in feet) after t seconds is given by the following. h=139-15t-16t^2 how long after the ball is thrown does it hit the ground? round your answer(s) to the nearest hundredth. (if there is more than one answer, use the "or" button.) t =

Solve 3x-18=2y and 5x-6y=6 by elimination show work

The graph shows the distance kerri drives on a trip. what is kerri's speed?