Answer:
Part A) The potato hit the ground at t=5.70 seconds (see the explanation)
Part B) The potato is 40 feet off the ground at the time t=5.28 seconds (see the explanation)
Step-by-step explanation:
we have
where
h(t) is the height of a potato in feet
t is the time in seconds
Part A) Write an equation that can be solved to find when the potato hits the ground. Then solve the equation
we know that
When the potato hit the ground, the value of h(t) must be equal to zero
so
For h(t)=0
Solve the quadratic equation
The formula to solve a quadratic equation of the form
is equal to
in this problem we have
so
substitute in the formula
therefore
The potato hit the ground at t=5.70 seconds
Part B) Write an equation that can be solved to find when the potato is 40 feet off the ground. Then solve the equation
For h(t)=40 ft
substitute in the quadratic equation
Solve the quadratic equation
we have
substitute in the formula
therefore
The potato is 40 feet off the ground at the time t=5.28 seconds