Question

[Bùi hải yến]

Tìm q,r thuộc N, sao cho 54 = 7q + r 

Answer 1

[Kiều Vũ Linh]

\(54=7q+r\)

\(\Rightarrow54-r=7q\)

Mà \(0\le r< 7\)

\(\Rightarrow7q\in\left\{54;53;52;51;50;49;48\right\}\)

\(\Rightarrow q\in\left\{\dfrac{54}{7};\dfrac{53}{7};\dfrac{52}{7};\dfrac{51}{7};\dfrac{50}{7};7;\dfrac{48}{7}\right\}\)

Mà \(q\in N\)

\(\Rightarrow q=7\Rightarrow r=54-7q=54-7.7=5\)

Vậy \(q=7;r=5\)

Answer 2

[Citii?]

\(54=7.7+5\)