SOLUTION: An astronaut on the moon throws a baseball upward. The astronaut is 6ft, 6 in tall, and the initial velocity of the ball is 40 ft per second. The height s of the ball in feet is gi

Algebra ->  Equations -> SOLUTION: An astronaut on the moon throws a baseball upward. The astronaut is 6ft, 6 in tall, and the initial velocity of the ball is 40 ft per second. The height s of the ball in feet is gi      Log On


   



Question 1119803: An astronaut on the moon throws a baseball upward. The astronaut is 6ft, 6 in tall, and the initial velocity of the ball is 40 ft per second. The height s of the ball in feet is given by the equation s=-2.7t squared+40t+6.5, where t is the number of seconds after the ball was thrown. After how many seconds is the ball 22ft above the moons surface?
Answer by josmiceli(19441) About Me  (Show Source):
You can put this solution on YOUR website!
+s=+-2.7t+%5E2+%2B+40t+%2B+6.5+
+22+=+-2.7t%5E2+%2B+40t+%2B+6.5+
+2.7t%5E2+-+40t+%2B+15.5+=+0+
+27t%5E2+-+400t+%2B+155+=+0+
Solve for +t+ using quadratic formula
You will get 2 results. One is for when
The ball is on the way up and the other
Is for when the ball is going down