Explanation:
Given points
( 3 , - 9) and ( 6 , - 18 )
The equation of the line is
y - y1 = ( y2 - y1 / x2 - x1 ) ( x - x1)
y + 9 = ( - 18 + 9 / 6 - 3 ) ( x - 3 )
y + 9 = ( - 9 / 3 ) ( x - 3 )
y + 9 = - 3 ( x - 3 )
y + 9 + 3( x - 3 ) = 0
y + 9 + 3x - 9 = 0
y + 3x = 0
Is the required equation.
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