Answer :
Sure, let's solve the problem step-by-step.
We are given the equation for Jerald's height as a function of time:
[tex]\[ h = -16t^2 + 729 \][/tex]
where [tex]\( h \)[/tex] is the height in feet, and [tex]\( t \)[/tex] is the time in seconds.
We need to determine when Jerald's height is less than 104 feet, according to the options provided.
1. Set up the inequality:
We want to find when [tex]\( h < 104 \)[/tex].
[tex]\[ -16t^2 + 729 < 104 \][/tex]
2. Solve the inequality:
First, subtract 104 from both sides:
[tex]\[ -16t^2 + 729 - 104 < 0 \][/tex]
[tex]\[ -16t^2 + 625 < 0 \][/tex]
Now, let's isolate [tex]\( t^2 \)[/tex]:
Subtract 625 from both sides:
[tex]\[ -16t^2 < -625 \][/tex]
Divide both sides by -16 (when dividing by a negative number, the inequality sign reverses):
[tex]\[ t^2 > \frac{625}{16} \][/tex]
[tex]\[ t^2 > 39.0625 \][/tex]
3. Find the values of [tex]\( t \)[/tex]:
Take the square root of both sides to solve for [tex]\( t \)[/tex]:
[tex]\[ t > \sqrt{39.0625} \][/tex]
[tex]\[ t > 6.25 \][/tex]
4. Conclusion:
Jerald is less than 104 feet above the ground when [tex]\( t > 6.25 \)[/tex] seconds.
Based on the options provided, the correct interval is [tex]\( t > 6.25 \)[/tex].
We are given the equation for Jerald's height as a function of time:
[tex]\[ h = -16t^2 + 729 \][/tex]
where [tex]\( h \)[/tex] is the height in feet, and [tex]\( t \)[/tex] is the time in seconds.
We need to determine when Jerald's height is less than 104 feet, according to the options provided.
1. Set up the inequality:
We want to find when [tex]\( h < 104 \)[/tex].
[tex]\[ -16t^2 + 729 < 104 \][/tex]
2. Solve the inequality:
First, subtract 104 from both sides:
[tex]\[ -16t^2 + 729 - 104 < 0 \][/tex]
[tex]\[ -16t^2 + 625 < 0 \][/tex]
Now, let's isolate [tex]\( t^2 \)[/tex]:
Subtract 625 from both sides:
[tex]\[ -16t^2 < -625 \][/tex]
Divide both sides by -16 (when dividing by a negative number, the inequality sign reverses):
[tex]\[ t^2 > \frac{625}{16} \][/tex]
[tex]\[ t^2 > 39.0625 \][/tex]
3. Find the values of [tex]\( t \)[/tex]:
Take the square root of both sides to solve for [tex]\( t \)[/tex]:
[tex]\[ t > \sqrt{39.0625} \][/tex]
[tex]\[ t > 6.25 \][/tex]
4. Conclusion:
Jerald is less than 104 feet above the ground when [tex]\( t > 6.25 \)[/tex] seconds.
Based on the options provided, the correct interval is [tex]\( t > 6.25 \)[/tex].