Find the slope, if it exists, of the line containing the pair of points.?

Question

(8,4) and (9, -5)

M=???

Answer 1

-9x + 76 =y

Answer 2

remember slope intercept form:  y = (m)x + b

the definition of slope (m) is change in y / change in x...

Based on your points, slope = (y2-y1) / (x2-x1)

Slope (m) = (-5-4) / (9-8)  calculated...m = -9/1  slope = -9

If you need to find y-int (b), just choose a pair and plug in the numbers...say you chose (8,4), your formula would look like this:

4 = -9 (8) + b  which equals 4 = -72 + b ... 4 + 72 = b  

slope = -9, y-int = 76

Formula in slope intercept form is y = -9x + 76