Question

tìm các số nguyên x,y sao cho:

  (35x-4) chia hết cho (7x+1)

(x+1) nhân (y-2)=4

Answer 1

\(\left(35x-4\right)⋮\left(7x+1\right)\)

\(\Leftrightarrow\left(35x+5-9\right)⋮\left(7x+1\right)\)

\(\Leftrightarrow9⋮\left(7x+1\right)\)

\(\Leftrightarrow7x+1\inƯ\left(9\right)=\left\{-9;-3;-1;1;3;9\right\}\)

\(\Leftrightarrow x=0\)

\(\left(x+1\right)\left(y-2\right)=4\)

\(\Leftrightarrow x+1\inƯ\left(4\right)=\left\{-4;-2;-1;1;2;4\right\}\)

\(\Leftrightarrow x\in\left\{-5;-3;-2;0;1;4\right\}\)

\(\Leftrightarrow y\in\left\{1;0;-2;6;4;3\right\}\)