16t^2+64t+160 after how many seconds is the ball 100 feet off the ground's surface?

Grandma made an apple pie. josh and his brother joe finished 4/5 of it. then 3 friends came over and shared the left over. how much pie did each friend eat

Write an equation of the line that passes through 9,2 and is parallel to the line y=5/3x+9

In a two-digit number the units' digit is 7 more than the tens' digit. the number with digits reversed is three times as large as the sum of the original number and the two digits. find the number.