An object is dropped from a small plane. As the object falls, its distance, d, above the ground after t seconds, is given by the
formula d = -1612 + 1,000. Which inequality can be used to find the interval of time taken by the object to reach the height
greater than 300 feet above the ground?
-167 +1,000 <300

Respuesta :

The inequality can be used to find the interval of time taken by the object to reach the height  greater than 300 feet above the ground is:

[tex]d = -16t^2 + 1000[/tex]

Solution:

The object falls, its distance, d, above the ground after t seconds, is given by the  formula:

[tex]d = -16t^2 + 1000[/tex]

To find the time interval in which the object is at a height greater than 300 ft

Frame a inequality,

[tex]-16t^2 + 1000 > 300[/tex]

Solve the inequality

Subtract 1000 from both sides

[tex]-16t^2 + 1000 - 1000 > 300 - 1000\\\\-16t^2 > -700[/tex]

[tex]16t^2 < 700\\\\Divide\ both\ sides\ by\ 16\\\\t^2 < \frac{700}{16}\\\\Take\ square\ root\ on\ both\ sides\\\\t < \sqrt{\frac{700}{16}}\\\\t < \pm 6.61[/tex]

Time cannot be negative

Therefore,

t < 6.61

And the inequality used  is: [tex]-16t^2 + 1000>300[/tex]