Ryan went skydiving. He jumped out of the airplane at a height of 12,000 ft. His free-fall is modeled by the quadratic equation h(t) = -51t? +795t + 12,000. After free-falling for less than a minute, Ryan releases the parachute and his fall changes from a quadratic model to
a linear model: h(t) = -75t + 9000. For both models, let h(t) be Ryan's height at time t. What time did he release the parachute and how high was he?