What is the slopr of the line that contains the points (4,-1)and (-1,4)

Do,h = (7, 9) (14, 18) the scale factor is

Math i have no idea how to do a and b

The students at jefferson middle school are raising money for a charity by selling t-shirts and hats. the number of t-shirts sold was 3 times the number of hats. the profit was $5 for each t-shirt sold and $2.50 for each hat sold. the students raised $840 for the charity. they used the system below to analyze their success and found the solution to be (144, 48). 5x+2.50y=840 x=3y how much did they earn from t-shirt sales?