Đáp án:
Giải thích các bước giải:
$xy-\dfrac{x}{5}+\dfrac{y}{2}+y-12x=44$
$⇔\dfrac{10xy}{10}-\dfrac{2x}{10}+\dfrac{5y}{10}+\dfrac{10y}{10}-\dfrac{120x}{10}=\dfrac{440}{10}$
$ $
$⇔10xy-2x+5y+10y-120x=440$
$⇔10xy-122x+15y=440$
$⇔2x.(5y-61)+15y=440$
$⇔2x.(5y-61)+15y-183=440-183$
$⇔2x.(5y-61)+3.(5y-61)=257$
$⇔(2x+3).(5y-61)=257=257.1=1.257=(-1).(-257)=(-257).(-1)$
$TH1:(2x+3).(5y-61)=257.1$
$⇔x=127;y=\dfrac{62}{5}$
$TH2:(2x+3).(5y-61)=1.257$
$⇔x=-1;y=\dfrac{318}{5}$
$TH3:(2x+3).(5y-61)=(-1).(-257)$
$⇔x=-2;y=\dfrac{-196}{5}$
$TH4:(2x+3).(5y-61)=(-257).(-1)$
$⇔x=-130;y=12$
