A hovercraft takes off from a platform.Its height (in meters), x seconds after takeoff, is modeled by:h(x)=−3(x−3)2+108How many seconds after takeoff will the hovercraft land on the ground?seconds
Q. A hovercraft takes off from a platform.Its height (in meters), x seconds after takeoff, is modeled by:h(x)=−3(x−3)2+108How many seconds after takeoff will the hovercraft land on the ground?seconds
Understand the Problem: Understand the problem.We need to find the time when the hovercraft's height is 0, which means it has landed on the ground. The height is given by the function h(x)=−3(x−3)2+108.
Set Height Function: Set the height function equal to 0 to find when the hovercraft lands.0=−3(x−3)2+108
Solve for x: Solve for x.First, move the constant term to the other side of the equation:−3(x−3)2=−108
Isolate Squared Term: Divide both sides by −3 to isolate the squared term.(x−3)2=36
Solve for x: Take the square root of both sides to solve for x−3.x−3=±6
Discard Negative Value: Solve for x by adding 3 to both possible values of x−3. x=3+6 or x=3−6 x=9 or x=−3
Discard Negative Value: Solve for x by adding 3 to both possible values of x−3. x=3+6 or x=3−6 x=9 or x=−3Since time cannot be negative, we discard the negative value. The hovercraft will land on the ground after 9 seconds.
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