Answer:
Only C is a function
Step-by-step explanation:
To test whether a graph is a function you use the vertical line test.
If you can place a vertical line anywhere on the plane (in the domain of the "function" to be tested) and it intersects the curve at more than one point, the curve is not a function.
We see with A, wherever we put the vertical line it intersects twice.
With B, it intersects infinitely many times.
C is a function because wherever we put the vertical line, it only intersects once.
D is a function because it intersects twice providing we do not put it on the "tip" of the parabola.
The mathematical reasoning behind this is that a function must be well-defined, that is it must send every x-value to one specific y-value. There can be no confusion about where the function's input is going. If you look at graph B and I ask you what is f(3)? Is it 1? 2? 3? ... Who knows, it's not well-defined and so it's not a function. However if I ask you about C, whichever input value for x I give you, you can tell me to which y-value it gets mapped/sent to.
Answer:
90 hours
Step-by-step explanation:
The rate at which water enters the pool is
75 gallons
-------------------
1 hour
This is equivalent to
1 hour per 75 gallons, leading to:
1 hour
-------------------- * 6,750 gallons = 90 hours
75 gallons
The point on the unit circle corresponding to -180 degrees is
((x, y) = (-1, 0).
<span>tan(-180°) = y/x = 0/(-1) = 0</span>
Answer:
X = 4
Step-by-step explanation:
5x + 3 = 23
Subtract 3 from both sides: 5x = 20
Divide both sides by 5: x = 4
