SOLUTION: Without graphing, tell whether the graphs of each pair of equations are paralell. y = -7x-9 and -3y = 21x-9. I don't know how to go about showing my work step by step.
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Question 885428: Without graphing, tell whether the graphs of each pair of equations are paralell. y = -7x-9 and -3y = 21x-9. I don't know how to go about showing my work step by step. Answer by nerdybill(7384) (Show Source):
You can put this solution on YOUR website! Rearrange each equation into the "slope-intercept" form:
y = mx + b
where m is the slope.
.
y = -7x-9
this one is already in the form and the slope is -7
and
-3y = 21x-9
dividing both sides by -3
y = -7x + 3
slope is also -7
.
since BOTH equations have the same slope, they are parallel
