a ladder is laid against two walls. The higher wall is 3meters and the lower is 1meter high. if the foot of the ladder is 0.5meters from the lower wall, how far is it from the higher wall. how far are the walls​

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?