Answer :
Sure, let's work through the problem step-by-step to find out for which interval of time Jerald is less than 104 feet above the ground, given his height equation:
[tex]\[ h = -16t^2 + 729 \][/tex]
We need to determine the time [tex]\( t \)[/tex] when [tex]\( h < 104 \)[/tex] feet.
1. Start with the inequality:
[tex]\[ -16t^2 + 729 < 104 \][/tex]
2. Isolate the term involving [tex]\( t \)[/tex]:
[tex]\[ -16t^2 < 104 - 729 \][/tex]
3. Simplify the right side of the inequality:
[tex]\[ -16t^2 < -625 \][/tex]
4. Divide both sides by -16 (note that dividing by a negative number reverses the inequality sign):
[tex]\[ t^2 > \frac{625}{16} \][/tex]
5. Calculate the right side of the inequality:
[tex]\[ t^2 > 39.0625 \][/tex]
6. Take the square root of both sides to solve for [tex]\( t \)[/tex] (both positive and negative roots):
[tex]\[ t > \sqrt{39.0625} \][/tex]
[tex]\[ t > 6.25 \][/tex]
Since we are dealing with the context of time in seconds, a negative time wouldn't make sense for this scenario, so we only consider the positive root.
Therefore, Jerald will be less than 104 feet above the ground for:
[tex]\[ t > 6.25 \][/tex]
So, the correct interval is:
[tex]\[ \boxed{t > 6.25} \][/tex]
[tex]\[ h = -16t^2 + 729 \][/tex]
We need to determine the time [tex]\( t \)[/tex] when [tex]\( h < 104 \)[/tex] feet.
1. Start with the inequality:
[tex]\[ -16t^2 + 729 < 104 \][/tex]
2. Isolate the term involving [tex]\( t \)[/tex]:
[tex]\[ -16t^2 < 104 - 729 \][/tex]
3. Simplify the right side of the inequality:
[tex]\[ -16t^2 < -625 \][/tex]
4. Divide both sides by -16 (note that dividing by a negative number reverses the inequality sign):
[tex]\[ t^2 > \frac{625}{16} \][/tex]
5. Calculate the right side of the inequality:
[tex]\[ t^2 > 39.0625 \][/tex]
6. Take the square root of both sides to solve for [tex]\( t \)[/tex] (both positive and negative roots):
[tex]\[ t > \sqrt{39.0625} \][/tex]
[tex]\[ t > 6.25 \][/tex]
Since we are dealing with the context of time in seconds, a negative time wouldn't make sense for this scenario, so we only consider the positive root.
Therefore, Jerald will be less than 104 feet above the ground for:
[tex]\[ t > 6.25 \][/tex]
So, the correct interval is:
[tex]\[ \boxed{t > 6.25} \][/tex]