Quy đồng: mẫu số chung : 72
\(\frac{1}{18}=\frac{4}{72}\)
\(\frac{x}{12}=\frac{x}{72}\)
\(\frac{y}{9}=\frac{y}{72}\)
\(\frac{1}{4}=\frac{18}{72}\)
=>\(\frac{1}{12}=\frac{6}{72}\)
=>\(\frac{1}{9}=\frac{8}{72}\)
so sánh: \(\frac{1}{12}< \frac{1}{9}\) vì \(\frac{6}{72}< \frac{8}{72}\)
\(\Rightarrow x=1\) ; \(y=1\)
Tim cac so nguyen x,y biet
\(\frac{x}{4}=\frac{y}{7}va-y=9\)
Tim cac so nguyen x,y biet
\(\frac{x+3}{y-1}\) =\(\frac{3}{4}\)va x + y = 5
Tim cac so nguyen x,y biet
a) \(\frac{x}{4}=\frac{y}{7}\)va \(x-y=9\)
b) \(\frac{x}{2}=\frac{y}{5}\)va 3x - y =5
1. Cho Phan so B=\(\frac{n}{n-4}\)(voi n \(\in\)Z)
a. Tim So nguyen n de B la Phan so
b. Tim so Nguyen n de B co Gia tri la so tu nhien
2. Tim cac so nguyen x, y biet
a.\(\frac{x}{-3}=\frac{4}{y}\)
b. \(\frac{2}{x}=\frac{y}{-9}\)
Tim cac so nguyen x,y biet
a)\(\frac{x-3}{y-2}\)=\(\frac{3}{2}\)va x - y = 4
b)\(\frac{x+3}{y-1}\)=\(\frac{3}{4}\)va x + y = 5
Tim cac so nguyen x biet
a)\(\frac{x+2}{3}=\frac{2x-1}{5}\)
b)\(\frac{-x}{4}=\frac{-9}{x}\)
Tim cac so nguyen x,y biet
a)\(\frac{2x+1}{3}\) \(=\frac{4}{y}\)
b)\(\frac{x}{y}\) =\(\frac{2}{5}\)
Tim cac so nguyen x,y biet
\(\frac{x-3}{y-2}=\frac{3}{2}\) va x - y = 4