Question

tìm x biết :

\(\frac{1+2y}{18}=\frac{1+4y}{24}=\frac{1+6y}{6x}\)

 

Answer 1

\(\frac{1+2y}{18}=\frac{1+4y}{24}\Rightarrow24\left(1+2y\right)=18\left(1+4y\right)\Rightarrow24+48y=18+72y\Rightarrow24y=6\Rightarrow y=\frac{1}{4}\)

Thay y = 1/4 vào \(\frac{1+4y}{24}=\frac{1+6y}{6x}\) ta đc:

\(\Rightarrow\frac{1+\frac{4.1}{4}}{24}=\frac{1+\frac{6.1}{4}}{6x}\Rightarrow\frac{1}{12}=\frac{\frac{5}{2}}{6x}\Rightarrow6x=\frac{5}{2}.12=30\Rightarrow x=30:6=5\)

Vậy x = 5