B
buianhduc098
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a, ( 2x + 1 ) . ( y - 2 ) = 3
b, xy=5 và x - y = 4
c, ( x mũ 2 - 4 ) . ( -2y - 6 ) =0
d, xy+3x-7y-21 = 0
tKS kác pác tr'c ạh![Smile :) :)](data:image/gif;base64,R0lGODlhAQABAIAAAAAAAP///yH5BAEAAAAALAAAAAABAAEAAAIBRAA7)
b, xy=5 và x - y = 4
c, ( x mũ 2 - 4 ) . ( -2y - 6 ) =0
d, xy+3x-7y-21 = 0
tKS kác pác tr'c ạh