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:
8,840
Step-by-step explanation:
Multiply 4420 by 200% to get the answer 8840. You can also multiply 4420 by 2 to get the same answer as you would multiplying by 200%.
Replace the x in 7x by (3x + 1):-
(f o g)(x) = 7 * (3x + 1)
= 21x + 7 which is choice D.
Y=-4x+3 is already in slope intercept form. Graphed it looks like this
X=5.2
Hope this was helpful