Câu hỏi của Phạm Đức

Question

Tìm x,y biết

(2x-1).(2y-1)=-35

Phạm Ngân Hà · Accepted Answer

$\left(2x-1\right)\left(2y-1\right)=-35$

$\Rightarrow\left(2x-1\right)\left(2y-1\right)=\left(-1\right).35=35.\left(-1\right)=1.\left(-35\right)=\left(-35\right).1=5.\left(-7\right)=\left(-7\right).5=\left(-5\right).7=7.\left(-5\right)$

Ta có bảng sau:

$2x-1$
			$-1$
			$35$
			$1$
			$-35$
			$5$
			$-7$
			$-5$
			$7$

$2y-1$
			$35$
			$-1$
			$-35$
			$1$
			$-7$
			$5$
			$7$
			$-5$

$x$
			$0$
			$18$
			$1$
			$-17$
			$3$
			$-3$
			$-2$
			$4$

$y$
			$18$
			$0$
			$-17$
			$1$
			$-3$
			$3$
			$4$
			$-2$

Vậy $\left(x;y\right)=\left\{\left(0;18\right);\left(18;0\right);\left(1;-17\right);\left(-17;1\right);\left(3;-3\right);\left(-3;3\right);\left(-2;4\right);\left(4;-2\right)\right\}$Câu trả lời: $\left(2x-1\right)\left(2y-1\right)=-35$