Question 574557
Find an equation of the line in slope-intercept form that passes
through each given set of points. Show all your work.
(–2, 2) and (1, 5)
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Find the slope, m
m = diffy/diffx = (2-5)/(-2-1)
m = 1
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Use y = mx + b and either point to find b
5 = 1*1 + b
b = 4
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--> y = x + 4
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You can use determinants:
|+x y 1|
|-2 2 1| = 0
|+1 5 1|
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x*(2-5) - y*(-2-1) + 1*(-10-2) = 0
-3x + 3y = 12
x - y = -4
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Do these the same way.
(1, 7) and (3, 2)

(–3, 1) and (8, 1)