Question

Tìm các số nguyên \(x\) và \(y\), biết :

a) \(\dfrac{x}{7}=\dfrac{6}{21}\)

b) \(-\dfrac{5}{y}=\dfrac{20}{28}\)

Answer 1

a) x.21=6.7

x.21=42

x=42:21

x = 2

b) y . 20 = -5.28

y.20 = -140

y = (-140) : 20

y = -7

Answer 2

a)=>x*21=7*6

=>x*21=42

=>x=42/21

x=2

b)=>y*20=(-5)*28

=>y*20=-140

=>y=-140/20

y=-7

Answer 3

a)x/7=6/21

x.21=6.7

x.21=42

x=42:21

x=2

b)-5/y=20/28

y.20=-5.28

y.20=-140

y=-140:20

y=-7