00:01
An astronaut on the moon throws a baseball upward, baseball upward, and the astronaut is six feet, six inch tall, and the initial velocity of the ball is 30 feet per second.
00:12
The height of the ball is given by this particular equation.
00:16
We are the number of seconds after the ball was thrown.
00:19
So the question asks that after how many seconds of the ball 20 feet above the moon's surface.
00:25
So in short, we have to solve the equation that all the equation s is equal to 12.
00:31
So this means that s is negative 2 .70 square plus 30t plus 6 .5 is equal to 12.
00:40
Then subtracting 12 both sides, we have subtracting 12 both sides, we have this as 5 .5 and this is equal to 0.
00:49
And i think we can use the quadratic formula now because there are decimals and all.
00:54
It's not the usual integers.
00:57
So factorizing wouldn't be a great idea...