The equation y = -16t^2 - 80t + 54 describes the height (in feet) of a ball thrown downward at 80 feet per second from a height of 54 feet from the ground, where t represents time, measured in seconds. In how many seconds will the ball hit the ground? Express your answer as a decimal rounded to the nearest hundredth.
When the ball hits the ground, height = y will be ZERO
0 = - 16t^2 - 80t + 54 Use quadratic equation a = -16 b = -80 and c = 54 to solve for t
throe out the negative 't' value
\(t = {80 \pm \sqrt{(-80)^2-4(-16)(54)} \over 2(-16)}\)
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https://www.calculatorsoup.com/calculators/algebra/quadratic-formula-calculator.php