What is 16 * -4
what is -9 *-8

The sum of the speeds of two trains is 720.2 mph. if the speed of the first train is 7.8 mph faster than the second train, find the speeds of each.

Which expression is the factorization of x^2+10+21

Anew movie is released each year for 14 years to go along with a popular book series. each movie is 2 minutes longer than the last to go along with a plot twist. the first movie is 70 minutes long. use an arithmetic series formula to determine the total length of all 14 movies