Write (-3,3) and (1,2) in slope intercept form

Question

Point slope formula 

Answer 1

Hi Mariel,

 

Let's call the points (x1, y1) = (-3, 3) and (x2, y2) = (1, 2).

 

You want to write a linear formula of the form

 

y = mx + b

 

where m is the slope of the line and b is the y-intercept.

 

The slope  = Δy /  Δx = (y2 - y1)/(x2 - x1) = (2 - 3) / (1 - (-3)) = -1/4

 

The equation is now

 

y = (-1/4)x + b

 

We now solve for b.

 

b = y + (1/4)x

 

We can now insert for (x, y) either (x1, y1) or (x2, y2). I choose (x1, y1) = (-3, 3).

 

b = 3 + (1/4)(-3) = 12/4 - 3/4 = 9/4

 

This, the slope-intercept form of the equation that contains the two points given is

 

y = (-1/4)x + 9/4

Answer 2

I respectfully suggest that you will find hundreds of problems resembling this one, in our Resources/Answers.

Search, read & study. Then do.

 

What do you think would be the first step, based on the given information?

 

Then it's time to determine the second step.