Question 200627
(1)  7m +n = 27
(2)  m-8n = 69 ,,,,,,,m= (8n +69)
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subst  (2)  in  (1)
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7(8n+69) +n =  27
56n +483 +n = 27
57n = -456
n = -8
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subst  in  (2) m= (8n +69) = 8(-8) -69 = -64 +69 = 5
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Answer ,,,,,m=5,,,,n=-8
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check
(1) 7(5) +(-8) = 35 -8 = 27,,,,,ok
(2) (5) -8(-8) = 5+64 =69,,,,,,,,ok
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