Question

1/Tìm các số nguyên x,y:a)x/3=4/y b)x/y=4/y c)2/x=x/8

2/Rút gọn:

a)4x7/9x32 b)3x21/14x15 c)9x6-9x3/18 d)17x15-17/3-20 e)2x5x13/26x35 f)49+7x49/49

Answer 1

Bài 2: 

a: \(\dfrac{4\cdot7}{9\cdot32}=\dfrac{4}{32}\cdot\dfrac{7}{9}=\dfrac{1}{8}\cdot\dfrac{7}{9}=\dfrac{7}{72}\)

b: \(\dfrac{3\cdot21}{14\cdot15}=\dfrac{63}{210}=\dfrac{3}{10}\)

c: \(\dfrac{9\cdot6-9\cdot3}{18}=\dfrac{9\cdot3}{18}=\dfrac{3}{2}\)

d: \(\dfrac{17\cdot15-17}{3-20}=\dfrac{17\cdot14}{-17}=-14\)

e: \(=\dfrac{26\cdot5}{26\cdot35}=\dfrac{5}{35}=\dfrac{1}{7}\)

f: \(=\dfrac{49\left(1+7\right)}{49}=8\)