SOLUTION: Are the following lines parallel, perpendicular, or neither? L1 with equation x – 2y = 10 L2 with equation 2x + y = 2

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Question 124921: Are the following lines parallel, perpendicular, or neither? L1 with equation x – 2y = 10 L2 with equation 2x + y = 2
Found 2 solutions by stanbon, checkley71:
Answer by stanbon(75887) About Me  (Show Source):
You can put this solution on YOUR website!
Are the following lines parallel, perpendicular, or neither?
L1 with equation x – 2y = 10
L2 with equation 2x + y = 2
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Put both is slope-intercept form:
L1: y = (1/2)x-5
L2: y = -2x + 2
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The slopes are negative reciprocal of one another so the lines are perpendicular.
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Cheers,
Stan H.

Answer by checkley71(8403) About Me  (Show Source):
You can put this solution on YOUR website!
TO ANSWER THIS PROBLEM WE NEED TO FIND THE SLOPES OF THESE 2 LINES THUS:
Y=mX+b WHHERE m=SLOPE.
X-2Y=10 OR -2Y=-X+10 OR Y=-X/-2+10/-2 OR Y=X/2-5 (RED LINE)WHICH GIVES US A SLOPE=1/2.
2X+Y=2 OR Y=-2X+2 (GREEN LINE) WHICH GIVES US A SLOPE=-2.
SEEING AS THESE 2 SLOPES (1/2 & -2) ARE NEGATIVE RECIPRICALS OF EACH OTHER THEN THESE 2 LINES ARE PERPENDICULAR TO ONE ANOTHER.
PROOF:
+graph%28+300%2C+300%2C+-10%2C+10%2C+-10%2C+10%2C+y+=+x%2F2+-5%2C+y+=+-2x+%2B2%29+ (graph 300x300 pixels, x from -10 to 10, y from -10 to 10, of TWO functions y = x/2 -5 and y = -2x +2).