Equation of a parabola is written in the form of f(x)=ax²+bx+c.
The equation passes through points (4,0), (1.2,0) and (0,12), therefore;
replacing the points in the equation y = ax² +bx+c
we get 0 = a(4)²+b(4) +c for (4,0)
0 = a (1.2)²+ b(1.2) +c for (1.2,0)
12 = a(0)² +b(0) +c for (0,12)
simplifying the equations we get
16a + 4b + c = 0
1.44a +1.2b + c = 0
+c = 12
thus the first two equations will be
16a + 4b = -12
1.44 a + 1.2b = -12 solving simultaneously
the value of a = 5/2 and b =-13
Thus, the equation of the parabola will be given by;
y= 5/2x² - 13x + 12 or y = 2.5x² - 13x + 12
sorry for taking your points
Answer:
setup below, you'll have to do the final calculation
Step-by-step explanation:
first perform the operation in parenthesis
2+39= 41
then do the multiplication 3 x 41
in general do calculations in this order
1. Parenthesis
2. Multiplication
3. Division
4. Addition
5. Subtraction
working from left to right
Equation of a line:

m = gradient: The difference between two y points and two x points.

c = y-intercept: Where the line crosses the y-axis (x=0)
You have:

so you are missing the m and the c.
To calculate m find two y coordinates -you have (12,
<u>7</u>) and (0, <u>
1</u>)- and subtract them. Then divide this by the subtracted values of the x coordinates -you have (<u>
12</u>, 7) and (<u>
0</u>, 1)- This gives:



To calculate the c, you just see where the line crosses the y-axis. Because you have the point (0, 1), you know that when x=0, y=1. Because x=0 is on the y-axis, you can tell that the line passes through y=1. This makes your c = 1:

When you plug these values into the equation you get your answer:
If you ran 4km in 9 hours.
Then you'll run 24 km's in.
4km per 9 hours
8km per 18 hours.
12km per 26 hours.
16km per 34 hours.
20km per 40.
24km per 46.