Question 30191
If you have two points (x1,y1) and (x2,y2), then the slope of the line between these two points is given by 
m = (y1-y2)/(x1-x2)
Using the points given,(0,5) and (-3,-4)
m = (5 + 4)/(0 + 3)
m = 9/3
m = 3
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If two lines, with slopes m1 and m2, are perpindicular to each other, then the product of their slope is equal to minus 1,
m1*m2 = -1
So, if m1 = 3
then
m2 = -1/m1 = -1/3
m2 = -1/3
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