Answer: 
Step-by-step explanation:
The quadratic equation in its standard form is:

Now, we are given 5 points of the parabola (if you graph a quadratic equation you will have a parabola), however we only need to choose three points to find the coeficients
,
and
in the quadratic equation.
So, let's choose the first three points:
(-1,14):

(1)
(0,7):

(2)
(1,4):


(3)
Substituting (2) in (1) and (3):
(4)
(5)
At this point we have a system with two equations.
Adding (4) to (5):
(6)
Isolating
:
(7)
Substituitng (7) in (3):
(8)
Isolating
:
(9)
Now we have the three coeficients and we can write the quadratic equation:

Answer: C
Working out: (55,000 x 20) - (30,000 x 20) = $500,000
$1,100,000 - $600,000 =$500,000
10+.04(15)(.5)=10.30. 5+.12(15)(.5)=5.9. 10.3-5.9=4.4 the difference is 4.40 :)
Answer:
32 : 12 is the second equivalent ratio. = 48 : 18 is the third equivalent ratio. Therefore, the three equivalent ratios of 8 : 3 are 16 : 6, 32 : 12 and 48 : 18