Write the equation in slope-intercept form of the line that passes through the given points. (-1,3) and (-3,1)

Answer 1

Ok, eventually you are going to want your answer to end in this form y=mx+b where m is the slope and b is the y-intercept. So, we are going to begin by finding the slope which is the "m" part of the equation.

To find slope, you use this formula. m = (y₁- y₂)/ (x₁-x₂) It is important to keeps the coordinates in order and not mix them up here or you will get the wrong answer. I'm going to upload a video to explain better. Check that out above.

m = (3-1)/(-1- -3) = 2/ (-1+3) = 2/2 = 1

Ok, now we have our slope of 1

Let plug in the information we have.

y = 1x +b

So, we still need to find the y-intercept. the "b"

You can plug in either point to find the "b" or the y-intercept.

I'm going to choose (-1,3)

3= 1(-1) +b

3 = -1 +b

4 = b

Now we have all of the information for the line.

y = 1x + 4

You can do a quick check here and make sure that both of your points are really on this line. Just plug in both points and makes sure that they work with this line.

3 = 1 (-1) +4 Check

1 = 1 (-3) +4 Check

The equation of the line is y = 1x + 4

I hope this helps you! It is much easier to learn with video. I will have videos up very soon! Please look for the videos if you need extra help.

Answer 2

First, use the formula for finding the slope of the equation. The formula for finding the slope value given two (2) points is m=(y₂-y₁)/(x₂-x₁). For example: x₁=-1, y₁=3 and x₂=-3, y₂=1.

Second, use the point-slope equation to find the equation. The formula is (y-y₁)=m(x-x₁). You can either use the (-1,3) or (-3,1) to be the (x₁,y₁) value.