To find the equation of a line, you must first find the slope of the line. I will represent the slope with ‘m’.

m = ‘change in y’ divided by ‘change in x’, which is:

m = (y2-y1) / (x2-x1)

Now fill in the appropriate numbers for the variables and solve for m:

m = (2-2) / (4- (-9)) = 0 / 13 = 0

This means the slope of the line is zero.

Now you have to find the y-intercept, which I will call ‘b’ by using the slope-intercept form, which is y=mx+b.

Use either set of coordiantes to fill in the equation and solve for b:

y = mx+ b

2 = 0*4 + b

2 = b

This means the equation is:

y = 2

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When you see the coordinates (-9,2) and (4,2) you can realize that they both have a y-coordinate of 2. This means that the only way they can be in a line is if they are in a horizontal line. Therefore, the equation is y=2 and this makes a horizontal line.

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I hope my answers helped! 🙂