Question 185399
Write an equation in standard form for the line through the given points 
L (0,4) and M (-3 0) 
Find the slope m:
m = diffy/diffx = (4-0)/(0-(-3)) = 4/3
Then use either point:
y-y1 = m*(x-x1) where (x1,y1) is a point
y-0 = (4/3)*(x+3)
y = (4/3)x + 1  slope-intercept form
4x - 3y = -1 standard form
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Write an equation in standard form for the horizontal line and vertical line through each point. 
a) (4,5) 
Horizontal means constant y, so
y = 5
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Vertical means constant x, so
x = 4  (for any value of y, x is 4)
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Do the others the same way.
b) (-3,2) c) (1/2, 8) d) (9, -1/3)