You are jumping on a trampoline. Your height y (in feet) above the trampoline after t seconds can be represented by y=-16t^2+24t. How many seconds are you in the air?
+26387 You are jumping on a trampoline. Your height y (in feet) above the trampoline after t seconds can be represented by y=-16t^2+24t. How many seconds are you in the air?
\(\begin{array}{rcll} y&=&-16t^2+24t \qquad y(t) = 0\\ -16t^2+24t &=& 0 \\ t(\underbrace{-16\cdot t + 24}_{=0} ) &=& 0 \\\\ -16\cdot t + 24 &=& 0 \\ -16\cdot t + 24 &=& \qquad & | \qquad -24\\ -16\cdot t &=& - 24 \qquad & | \qquad : (-16)\\ t &=& \frac{-24}{-16} \\ t &=& \frac{24}{16} \\ t &=& \frac{3}{2} \\ t &=& 1.5\ \text{seconds} \\ \end{array}\)
