Need some help with 2 (Geo)
1 answer:
You might be interested in
Answer:
a) No. t < 0 is not part of the useful domain of the function
b) 2.0 seconds
Step-by-step explanation:
a) A graph of the function is shown below. It shows t-intercepts at t=-0.25 and t=2.0. We presume that t is measured forward from some event such as the ball being thrown or hit. The model's predicted ball location has no meaning prior to that event, when values of t are negative.
__
b) It is convenient to use a graphing calculator to find the t-intercepts. Or, the equation can be solved for h=0 any of several ways algebraically. One is by factoring.
h = 0 = -16t² +28t +8 . . . . . . . . . . . . the ball hits the ground when h = 0
0 = -4(4t² -7t -2) = -4(4t +1)(t -2)
This has t-intercepts where the factors are zero, at t=-1/4 and t=2.
The ball will hit the ground after 2 seconds.
Answer: The length and width are 50 and 30 meters (or 30 and 50 meters).
Step-by-step explanation:
To solve this question, we can represent variables for the length and width in two equations.
To solve for one of the variables, you'll have to substitute one of the variables, so solve for one of them:
Now, we have a standard quadratic equation that we can factor. When factoring, you'll get this:
This tells us that the width could be either 50 or 30.
Substitute 50 into one of the equations to find the length:
2 (l) + 100 = 160
l = 30.
The length and width are 50 and 30 meters (or 30 and 50 meters).