Which pair of lines are parallel? A. Y - 2x = - 5 and 2x - y = - 6 B. 2x + y = - 5 and 2x - y = - 6 C. Y - 2x = - 5 and 2x + y = 6 D. 2x + y = - 5 and 2x + y = 6

It would be choice "D". When you change all these equations into slope-intercept form (Y=mx+b or Y equals the slope times "X" plus the y-intercept), choice "D" is the only one with the same slope which is the the value of "m" in slope-intercept form. In this case, when both equations in choice "D" is changed to slope-intercept form, both equations' slopes become - 2. When slopes of two equations are the same, the lines are parallel to each other when graphed.