Amir stands on a balcony and throws a ball to his dog, who is at ground level. The ball's height (in meters above the ground), x seconds after Amir threw it, is modeled by: h(x)=−(x−2)2+16 How many seconds after being thrown will the ball hit the ground? seconds
Q. Amir stands on a balcony and throws a ball to his dog, who is at ground level. The ball's height (in meters above the ground), x seconds after Amir threw it, is modeled by: h(x)=−(x−2)2+16 How many seconds after being thrown will the ball hit the ground? seconds
Understand the problem: We need to find the time when the ball's height is 0, which means when it hits the ground.
Set height equation: Set the height equation equal to zero to find when the ball hits the ground.0=−(x−2)2+16
Solve equation for x: First, move the term 16 to the other side of the equation to isolate the squared term. −(x−2)2=−16(x−2)2=16
Take square root: Take the square root of both sides to solve for x. (x−2)2=16x−2=±4
Solve for x: Solve for x by adding 2 to both possible values of the square root.x=2+4 or x=2−4x=6 or x=−2
Interpret results: Since time cannot be negative, we discard the negative value.The ball will hit the ground 6 seconds after being thrown.
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