A smart-phone is thrown upwards from the top of a 672-foot

Last updated: 7/14/2022

A smart-phone is thrown upwards from the top of a 672-foot building with an initial velocity of 16 feet per second. The height h of the smart-phone after t seconds is given by the quadratic equation h=16t² + 16t+672. When will the smart-phone hit the ground? seconds