Answer:
432 people on Friday and 658 on Saturday
Step-by-step explanation:
Lets use variables for each day
x=Friday and y=Saturday
now write two equations since you were given two different information (money and people)
$6 on Friday and $8 on Saturday with a total amount of $7856
the equation will be 6x+8y=7856
now the second equation will be for people
x amount of people on Friday and y amount of people on saturday for a total of 1090; the equation will be
x+y=1090
put them together
6x+8y=7856
x+y=1090
now you can cancel a variable but manipulating one of the equations. We'll use x, to cancel x you need make it zero so multiply the bottom by -6
6x+8y=7856
-6(x+y=1090)
6x+8y=7856 now subtract downwards, with the x cancelling
-6x-6y=-6540
2y=1316 simplify
(2y/2)=(1316/2)
y=658
insert y into x+y=1090
x+(658)=1090
-658 -658
x=432
Just look at the x axis (horizontal) and see where x=1 or go 1 unit from the origin (0,0), then go up untill you hit a point that coresponds witha y value which looks to be 2 so coresponding y for x=1 is y=2
if we are given point (1,2) then
(x,y)
x=1
y=2
that is the solution already
Answer:
![f(x) = 4x^2 - 3x + 6](https://tex.z-dn.net/?f=%20f%28x%29%20%3D%204x%5E2%20-%203x%20%2B%206%20)
Step-by-step explanation:
Quadratic function is given as ![f(x) = ax^2 + bx + c](https://tex.z-dn.net/?f=%20f%28x%29%20%3D%20ax%5E2%20%2B%20bx%20%2B%20c%20)
Let's find a, b and c:
Substituting (0, 6):
![6 = a(0)^2 + b(0) + c](https://tex.z-dn.net/?f=%206%20%3D%20a%280%29%5E2%20%2B%20b%280%29%20%2B%20c%20)
![6 = 0 + 0 + c](https://tex.z-dn.net/?f=%206%20%3D%200%20%2B%200%20%2B%20c%20)
![c = 6](https://tex.z-dn.net/?f=%20c%20%3D%206%20)
Now that we know the value of c, let's derive 2 system of equations we would use to solve for a and b simultaneously as follows.
Substituting (2, 16), and c = 6
![f(x) = ax^2 + bx + c](https://tex.z-dn.net/?f=%20f%28x%29%20%3D%20ax%5E2%20%2B%20bx%20%2B%20c%20)
![16 = a(2)^2 + b(2) + 6](https://tex.z-dn.net/?f=%2016%20%3D%20a%282%29%5E2%20%2B%20b%282%29%20%2B%206%20)
![16 = 4a + 2b + 6](https://tex.z-dn.net/?f=%2016%20%3D%204a%20%2B%202b%20%2B%206%20)
![16 - 6 = 4a + 2b + 6 - 6](https://tex.z-dn.net/?f=%2016%20-%206%20%3D%204a%20%2B%202b%20%2B%206%20-%206%20)
![10 = 4a + 2b](https://tex.z-dn.net/?f=%2010%20%3D%204a%20%2B%202b%20)
![10 = 2(2a + b)](https://tex.z-dn.net/?f=%2010%20%3D%202%282a%20%2B%20b%29%20)
![\frac{10}{2} = \frac{2(2a + b)}{2}](https://tex.z-dn.net/?f=%20%5Cfrac%7B10%7D%7B2%7D%20%3D%20%5Cfrac%7B2%282a%20%2B%20b%29%7D%7B2%7D%20)
![5 = 2a + b](https://tex.z-dn.net/?f=%205%20%3D%202a%20%2B%20b%20)
=> (Equation 1)
Substituting (3, 33), and c = 6
![f(x) = ax^2 + bx + x](https://tex.z-dn.net/?f=%20f%28x%29%20%3D%20ax%5E2%20%2B%20bx%20%2B%20x%20)
![33 = a(3)^2 + b(3) + 6](https://tex.z-dn.net/?f=%2033%20%3D%20a%283%29%5E2%20%2B%20b%283%29%20%2B%206%20)
![33 = 9a + 3b + 6](https://tex.z-dn.net/?f=%2033%20%3D%209a%20%2B%203b%20%2B%206%20)
![33 - 6 = 9a + 3b + 6 - 6](https://tex.z-dn.net/?f=%2033%20-%206%20%3D%209a%20%2B%203b%20%2B%206%20-%206%20)
![27 = 9a + 3b](https://tex.z-dn.net/?f=%2027%20%3D%209a%20%2B%203b%20)
![27 = 3(3a + b)](https://tex.z-dn.net/?f=%2027%20%3D%203%283a%20%2B%20b%29%20)
![\frac{27}{3} = \frac{3(3a + b)}{3}](https://tex.z-dn.net/?f=%20%5Cfrac%7B27%7D%7B3%7D%20%3D%20%5Cfrac%7B3%283a%20%2B%20b%29%7D%7B3%7D%20)
![9 = 3a + b](https://tex.z-dn.net/?f=%209%20%3D%203a%20%2B%20b%20)
=> (Equation 2)
Subtract equation 1 from equation 2 to solve simultaneously for a and b.
![3a + b = 9](https://tex.z-dn.net/?f=%203a%20%2B%20b%20%3D%209%20)
![a = 4](https://tex.z-dn.net/?f=%20a%20%3D%204%20)
Replace a with 4 in equation 2.
The quadratic function that represents the given 3 points would be as follows:
![f(x) = ax^2 + bx + c](https://tex.z-dn.net/?f=%20f%28x%29%20%3D%20ax%5E2%20%2B%20bx%20%2B%20c%20)
![f(x) = (4)x^2 + (-3)x + 6](https://tex.z-dn.net/?f=%20f%28x%29%20%3D%20%284%29x%5E2%20%2B%20%28-3%29x%20%2B%206%20)
![f(x) = 4x^2 - 3x + 6](https://tex.z-dn.net/?f=%20f%28x%29%20%3D%204x%5E2%20-%203x%20%2B%206%20)
There are 9 long distance male runners and 5 long distance female runners. This makes a total of 9+5 = 14 long distance runners.
Out of this total of 14 long distance runners, there are 9 males. So the probability as a fraction is 9/14
If you need the answer in decimal form, then use a calculator to get 9/14 = 0.642857 which is approximate.