Question 211859
x +2y = 5
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2y = -x +5
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y = (-1/2)x +(5/2),,,,,,,original  line,,,m=-1/2,  b=5/2,,
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new parallel  line  has  same  slope
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y=mx+b,,,,y= (-1/2)x +b
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subst  (3,7),,,,,7= (-1/2)(3) +b,,,,b=8.5
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or  new  eqn is  y=(-1/2)x +8.5
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check,,,(3,7),,,7 = -1/2*3 +8.5 = 7 ,,,,,ok