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Question 116447: I have no clue how to do this problem can someone please help?
Solve the equations by graphing: y=5x-7
y-5x=8
Answer by checkley71(8403)   (Show Source):
You can put this solution on YOUR website! Y=5X-7 (RED LINE)
THIS LINE HAS A SLOPE OF 5 & A Y INTERCEPT OF (0,-7)
TO FIND ANOTHER POINT SET Y=0 & SOLVE FOR X
0=5X-7
5X=7
X=7/5 WHICH IS THE X INTERCEPT (7/5,0)
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Y-5X=8 (GREEN LINE)
Y=5X+8 HERE WE ALSO HAVE A SLOPE OF 5 WITH A Y INTERCEPT OF(0,8)
TO FIND ANOTHER POINT. SET Y=O & SOLVE FOR X
0=5X+8
5X=-8
X=-8/5 WHICH IS THE Y INTERCEPT (-8/5,0)
 (graph 300x200 pixels, x from -6 to 5, y from -10 to 10, of TWO functions y = 5x -7 and y = 5x +8).
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so I'm just wondering if the answer would be 1.5, 0.5 or 0.5, 1.5
I think it's 1.5, 0.5 could you tell me if I'm correct?
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THERE IS NO SOLUTION TO THESE 2 LINES VIA GRAPHING BECAUSE THEY DO NOT INTERSECT.
THERE IS ALSO NO ALGEBRAIC SOLUTION:
Y=5X-7 USING (5X-7) FOR Y IN THE OTHER EQUATION PROVES THIS POINT:
(5X-7)-5X=8
5X-5X=8+7
0=15 IS NOT A SOLUTION.
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