Answer:
![C(x)=35x+50](https://tex.z-dn.net/?f=C%28x%29%3D35x%2B50)
Electrician's fee: $50.
Charges per hour: $35
Step-by-step explanation:
Let x represent number of hours and y represent amount charged.
We have been given that an electrician charges $120 after 2 hours of work and $190 after 4 hours of work.
We can represent this information with two points as (2,120) and (4,190).
First of all, we will find slope using these points.
![m=\frac{y_2-y_1}{x_2-x_1}](https://tex.z-dn.net/?f=m%3D%5Cfrac%7By_2-y_1%7D%7Bx_2-x_1%7D)
Now, we will slope-intercept form of equation
to get our required equation as:
![y=35x+b](https://tex.z-dn.net/?f=y%3D35x%2Bb)
Substitute coordinates of point (2,120) to find the y-intercept.
![120=35(2)+b](https://tex.z-dn.net/?f=120%3D35%282%29%2Bb)
![120=70+b](https://tex.z-dn.net/?f=120%3D70%2Bb)
![120-70=70-70+b](https://tex.z-dn.net/?f=120-70%3D70-70%2Bb)
![50=b](https://tex.z-dn.net/?f=50%3Db)
Therefore, our required function would be
.
The electrician's fee would be $50 as it the initial amount or y-intercept.
The electrician charges $35 per hour as the slope of the line is 35.
You reflect point A over the x-axis, double the distance from point a to the x-axis, then give the coordinates.
ex/ point A to the x-axis: 6, reflection: 12. coordinates (-6, 5)
Answer:
3 hours
Step-by-step explanation:
The pool was filled at noon = ![\frac{1}{3}](https://tex.z-dn.net/?f=%5Cfrac%7B1%7D%7B3%7D)
After
hours the fool was filled = ![\frac{3}{4}](https://tex.z-dn.net/?f=%5Cfrac%7B3%7D%7B4%7D)
So,water filled in pool in
hours = ![\frac{3}{4}-\frac{1}{3}](https://tex.z-dn.net/?f=%5Cfrac%7B3%7D%7B4%7D-%5Cfrac%7B1%7D%7B3%7D)
So,water filled in pool in
hours = ![\frac{5}{12}](https://tex.z-dn.net/?f=%5Cfrac%7B5%7D%7B12%7D)
of pool is filled in hours =
Whole pool is filled in hours =
Whole pool is filled in hours =
Hence it took 3 hours the pump to fill the pool .
The data is equally spaced in x so let's start by taking first differences.
4-9 = -5
-1-4 = -5
-6 - -1 = -5
-11 - -6 = -5
Hmmm. I detect a pattern. That tells us we have a line and the slope is -5.
We read off the y intercept from x=0 as -1.
So our equation in slope intercept form is
y = -5 x - 1
or as a function
![f(x) = -5x -1](https://tex.z-dn.net/?f=%20f%28x%29%20%3D%20-5x%20-1%20)