Answer:
22 2/9
Step-by-step explanation:
When z "varies jointly" with x and y, it can be described by the formula
z = kxy
Here, we have bags of mulch (n) varying jointly with area (a) and depth (d), both in feet. The given information can let us find the value of k.
n = kad
10 = k·(120)(1/4)
10/30 = k = 1/3 . . . . . divide by the coefficient of k
Now, we can fill in the other values of interest.
n = (1/3)·(200)·(1/3) = 200/9
n = 22 2/9
You need 22 2/9 bags of mulch to cover 200 ft² to a depth of 4 inches.
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<em>Comment on the problem</em>
This problem requires the formula be written with both area and depth expressed in feet, yet it gives depth in inches. The formula can also be written using depth in inches. In that case, k = 1/36.
the
complete question in the attached figure
part A
the x intercept 0 is the point where the ball was hit, the x intercept 20 is the point where the ball fell back to the ground, 20 feet away from the kicker.
<span>the function is increasing in the interval x∈(0, 10) and decreasing in x∈(10, 20) </span>
this means that the height is increasing in the interval (0, 10) and decreasing as x goes through the interval (10,20)
the distance from the kicker is increasing during the whole interval (0, 20)
part B
the rate of change represents the slope of the secant line from A to B. It approximates the rate at which f(x) decreases or increases in the interval
x =[A, B]
from x = 22 to x = 26-------------- > the function does not exist