A baseball will reach height h feet after t seconds, as estimated by the formula
h(t) = 2 + 90t - 16t^2
At what time(s) will the baseball be 76 feet high? (Explain how you got the answer/show work in the space provided)

A baseball will reach height h feet after t seconds as estimated by the formula ht 2 90t 16t2 At what times will the baseball be 76 feet high Explain how you go class=

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Answer:

[tex]t = 1,\dfrac{37}{8} \text{ sec}[/tex]

Step-by-step explanation:

We are given the equation h(t) i.e. height h feet in time t:

[tex]h(t) = 2 + 90t - 16t^2[/tex]

We are given that value of h(t) is 76 feet and have to find the value of t.

[tex]\Rightarrow 76=2 + 90t - 16t^2\\\Rightarrow 74= 90t - 16t^2\\\Rightarrow 16t^2 -90t +74=0\\\Rightarrow 8t^2 -45t +37=0\\[/tex]

Using factorization method to solve the above quadratic equation:

We know that 45t = 8t + 37t :

[tex]\Rightarrow 8t^2 - 8t - 37t +37 =0\\\Rightarrow 8t(t - 1) - 37(t -1) =0\\\Rightarrow (t - 1)(8t - 37) =0\\\Rightarrow t =1 \text { or } \dfrac{37}{8}[/tex]

At time , [tex]\text{t = 1 sec or }\frac{37}{8} \text{ sec}[/tex] , the height of baseball will be 76 feet.