# Use the point-slope form to write an equation of a line through the given points

This form is given by the equation: ## Related Calculators:

We have learned how to get input from the user, and how to send information to the user. We have learned how to control commands with both for loops and while loops. We are well on our way to building some really powerful projects.

The thing is, so far all of our commands to the arduino pins have in effect been to either turn the pin On or turn it Off. The truth is that most times we want something in the middle. We would maybe want a voltage of 2. The arduino pins with the squiggly line by them are able to write these in between voltages.

These are pins 3,5,6,9,10,11 on the arduino uno. In the world of engineering and electronics, we say that we want an analog voltage.

That is, we want to apply any voltage we want, not just 0 or 5. To output an arbitrary voltage between 0 and 5, would issue the arduino an analogWrite command. Unfortunately, the arguments for the analogWrite command are not as simple as telling it a number between 0 and 5.

We must give it an integer between 0 and If we issued the command analogWrite mypin,0it would apply 0 volts to mypin. If we issued the command analogWrite mypin,it would appy 5 volts to the pin. As you can see, if we gave the command analogWrite mypin,we would get about 2.

You can see those are the easy ones, but in order to figure out exactly what value we should use for exactly the voltage we want, we will need to do some math.

Remember all the times you had to calculate the equation of a line in math? Well you are going to do it for real now and for a reason. We need to get an equation that will allow us to calculate the Write Value we should use to get the Voltage You will need to choose the correct value between 0 and to get your desired voltage You can see that you need the equation for the line above.

You have two points so can calculate the equation of the line. The first point is 0,0that is to say, that if you want a voltage of 0 to be applied to the pin, you should analogWrite the value of 0, as we explained above.

The second point is 5,that is to say, if you want to apply a voltage of 5 Volts, you should analogWrite the valueas explained above.Write an equation for a line that passes through the following points: (-4,4) and (6,9) Solution As you can see, point-slope form is pretty easy to use once you .

## SparkNotes: Writing Equations: Point-Slope Form

Example 1: Write an equation of the following line in point-slope form: Graph of a Line First, find the slope using the points (- 2, 3) and (3, - 1): m = = = -.

Since the slope of a vertical line is undefined you can't write the equation of a vertical line using neither the slope-intersect form or the point-slope form. But you can express it using the standard form. Find (a) the equation of a line that is parallel to the given line and includes the given point, and (b) the equation of a line that is perpendicular to the given line through the given point.

Write both answers in slope-intercept form. How To: Given two points on a line and a third point, write the equation of the perpendicular line that passes through the point. Determine the slope of the line passing through the points.

Find the negative reciprocal of the slope. This form consists of a pair of equations; the first equation gives the x coordinate and the second equation gives the y coordinate of a point on the line as functions of a parameter t.

(x 1, y 1) is a known point on the line and m is the slope of the line.

Point Slope Form