If i have 5,5,5,5=30 how ??

Describe the possible echelon forms of the standard matrix for a linear transformation t where t: set of real numbers is onto.

Find the number of real number solutions for the equation. x2 + 5x + 7 = 0 0 cannot be determined 1 2

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.