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:
$31.5
Step-by-step explanation:
Answer:
Reject the null hypothesis.
Step-by-step explanation:
n1 = 16
n2 = 21
S.V1 = 5.8
S.V2 = 2.4
= 0.05
= Population Variance 1 ≤ Population Variance 2
= Population Variance 1 > Population Variance 2
Test statistic value = 5.8 / 2.4 = 2.417
Degrees of freedom is n - 1
15 and 20
Critical value is 
= 2.2
2.417 > 2.2
we reject the null hypothesis as the critical value is greater than the test statistic.
Answer:
-17/14
Step-by-step explanation:
To subtract fractions, you must have a common denominator. If that is not given, you make it.
You do so buy finding the LCM of denominators:
LCM of 7 and 2 = 14
Now, here you have multiplied the denominators either by 7 or 2. You do the same for the respective numerators:
2x2/14 - 3x7/14 = 4/14 - 21/14.
Now that you have the same denominator, subtract the numerators:
4-21 = - 17
Put it back as a fraction : -17/14
hope this helps.
