the height, in meters, above the ground of a projectile is modeled by the function (f(t)=-4.9t^{2}+19.6t +…

the height, in meters, above the ground of a projectile is modeled by the function (f(t)=-4.9t^{2}+19.6t + 50), where (t) is the number of seconds since the object was launched. how long after launch does the projectile reach its maximum height?\na. 1 second\nb. 2 seconds\nc. 4 seconds\nd. 19.6 seconds\ne. 50 seconds
Answer
Explanation:
Step1: Identify the function type
The function $f(t)=-4.9t^{2}+19.6t + 50$ is a quadratic function in the form $y = ax^{2}+bx + c$, where $a=-4.9$, $b = 19.6$ and $c = 50$.
Step2: Recall the formula for the vertex of a quadratic function
The $t$-coordinate of the vertex of a quadratic function $y=ax^{2}+bx + c$ is given by $t=-\frac{b}{2a}$.
Step3: Substitute the values of a and b
Substitute $a=-4.9$ and $b = 19.6$ into the formula $t=-\frac{b}{2a}$. We have $t=-\frac{19.6}{2\times(-4.9)}=\frac{19.6}{9.8}=2$.
Answer:
B. 2 seconds