Hey!
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First, find the slope.
y2-y1/x2-x1
-20-(-5)/21-16
-15/5
-3
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Second, find the y-intercept.
We can solve for b with one of the points.
Put into slope-intercept form,
y = -3x + b
Substitute x and y with (16, -5)
-5 = -3(16) + b
-5 = -48 + b
-5 + 48 = -48 + b + 48
43 = b
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Third, put in slope-intercept form.
y = mx + b
m = slope
b = y-intercept
y = -3x + 43
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Hope This Helped! Good Luck!
