Two parallel lines have same slopes so we need to find the slope of the line which passes through the given points.
Suppose : A = ( - 2 , 7 ) & B = ( 4 , 4 )
Slope = y ( B ) - y ( A ) / x ( B ) - x ( A )
Slope = 4 - 7 / 4 - ( - 2 )
Slope = - 3 / 4 + 2
Slope = - 3 / 6
Slope = - 1 / 2
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As you know The coefficient of x is the slope of the line in slope-intercept form.
Thus we have to find the option which x has - 1 / 2 as the coefficient .
Look we have that in D so the correct answer is D .