I dont know the answer so please help me

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

Someone this asap for a group of students attends a basketball game. * the group buys x hot dogs at the concession stand for $2 each. * the group buys y drinks at the concession stand for $3 each. the group buys 29 items at the concession stand for a total of $70. how many hot dogs did the group buy?

Which shows the first equation written in slope-intercept form? 1/2 (2y + 10) = 7x