Question

How do you write the equation of a line if you know two points that are on the line?

Answer 1

y= mx +b,  where m is considered the slope. Hope this helps.

Answer 2

To write a equation of a line if you know two points that are on the line, you would first have to find the slope using the formula:

(y2 - y1) / (x2 - x2)

This would help you find the slope

You should always know that the standard form is y = mx + b

m = slope

plug in 2 of your points to the x and y values with your x like this:

(one y point) = (slope) (one x point) + b

This would help you to find the b of the equation

now you can write your equation like this:

y = (slope)x + (y - intercept you just found)

Here is a example using the points (1,2), (4,3)

Find your slope:

(3-2) / (4 - 1) =

1/3 = m(slope)

Now plug (I would be using points (1,2):

2 = 1/3(1) + b

2 = 1/3 + b

1 2/3 = b

Now you found your y - intercept:

y = 1/3m + 1 2/3