Rajani kicks a football. Its height in feet is given by h=−16t2+24t where t represents the time in seconds after kick. How many seconds have gone by when the football is at its highest point?Answer: seconds
Q. Rajani kicks a football. Its height in feet is given by h=−16t2+24t where t represents the time in seconds after kick. How many seconds have gone by when the football is at its highest point?Answer: seconds
Identify values of a, b, c: Identify the values of a, b, and c in the quadratic equationh=−16t2+24t. The equation is in the form at2+bt+c, where a=−16, b=24, and b0 (since it is not written, it is implied that b1).
Find vertex time: Find the t-coordinate of the vertex of the parabola, which represents the time at which the football reaches its maximum height.The formula for the t-coordinate of the vertex in a quadratic equation at2+bt+c is t=−2ab.Substitute a=−16 and b=24 into the formula: t=−2∗(−16)24.
Calculate time: Calculate the time at which the football reaches its maximum height. t=−2⋅(−16)24=−32−24=3224=0.75
Round to nearest second: Round the answer to the nearest second.The time at which the football reaches its maximum height is 0.75 seconds, which rounds to 1 second when considering the nearest whole second.
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