Step 1: Option (A) Expansion: The given function for the height of the football is h(t)=−4.9t2+19.6t. We need to find an equivalent expression that displays the hang time as a constant or coefficient. To do this, we will look at each option and see if it can be rearranged or simplified to show the hang time in the desired form.
Step 2: Option (B) Expansion: Let's start with option (A): −4.9(t−2)2+19.6. We can expand this expression to see if it simplifies to the original function.Expanding (t−2)2 gives t2−4t+4. Multiplying by −4.9 gives −4.9t2+19.6t−19.6. Adding 19.6 to this expression does not give us the original function, so option (A) is not equivalent to the original function.
Step 3: Option (C) Expansion: Next, we consider option (B): −4.9t(t−4). Expanding this expression gives −4.9t2+19.6t. This is exactly the original function, so option (B) is equivalent to the original function. However, it does not display the hang time as a constant or coefficient.
Step 4: Option (D) Expansion: Now, let's look at option (C): −4.9(t−3)2−9.8t+4. Expanding (t−3)2 gives t2−6t+9. Multiplying by −4.9 gives −4.9t2+29.4t−44.1. Adding −9.8t+4 to this does not simplify to the original function, so option (C) is not equivalent to the original function.
Step 4: Option (D) Expansion: Now, let's look at option (C): −4.9(t−3)2−9.8t+4. Expanding (t−3)2 gives t2−6t+9. Multiplying by −4.9 gives −4.9t2+29.4t−44.1. Adding −9.8t+4 to this does not simplify to the original function, so option (C) is not equivalent to the original function.Finally, we examine option (D): −4.9(t−1)2+9.8t+4. Expanding (t−1)2 gives t2−2t+1. Multiplying by −4.9 gives (t−3)20. Adding (t−3)21 to this expression gives us (t−3)22, which is the original function. However, this expression also does not display the hang time as a constant or coefficient.
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