Question

Bài 1 giải hệ pt

a, \(\begin{cases}\frac{x+y}{3}-\frac{x-y}{3}=\frac{14}{3}\\3x-\frac{y}{2}+\frac{x}{4}=24\end{cases}\)

Answer 1

\(\begin{cases}\frac{x+y}{3}-\frac{x-y}{3}=\frac{14}{3}\left(1\right)\\3x-\frac{y}{2}+\frac{x}{4}=24\left(2\right)\end{cases}\).Từ \(\left(1\right)\Rightarrow\frac{2y}{3}=\frac{14}{3}\)

\(\Rightarrow2y=14\Rightarrow y=7\) thay vào (2) ta có:

\(3x-\frac{7}{2}+\frac{x}{4}=24\Rightarrow3x+\frac{x}{4}=24+\frac{7}{2}\)

\(\Rightarrow\frac{13x}{4}=\frac{55}{2}\Rightarrow13x\cdot2=55\cdot4\)

\(\Rightarrow26x=220\Rightarrow x=\frac{220}{26}=\frac{110}{13}\)

Vậy hệ pt có nghiệm là \(x=\frac{110}{13};y=7\)