Answer
To find the slope of a line parallel
1. Calculate the line slope
The slope m = ( y2 - y1 ) / ( x2 - x1 )
You can select two different point
For example,
(x1 , y1 ) = (-4, 0)
(x2, y2 ) = (0, 6)
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So then, the slope,
m = ( y2 - y1 ) / ( x2 - x1 )
Replacing with the two points chosen
m = ( 6 - 0) / ( 0 - (-4) )
m=6/4
m= 3/2
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The parallel lines have the same slope.
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The slope of a line parallel to the given line is 3/2