Question

 

tìm x biết

a,\(|5x+\frac{3}{4}|-\frac{5}{4}=2\)

b,\(\frac{3}{2}-|\frac{1}{2}x+1|=\frac{1}{4}\)

cac ban lam on giup minh lam nhanh nhe

 

Answer 1

a/ \(\left|5x+\frac{3}{4}\right|-\frac{5}{4}=2\)

\(\left|5x+\frac{3}{4}\right|=\frac{13}{4}\)

/ \(5x+\frac{3}{4}=\frac{13}{4}\)
\(5x=\frac{5}{2}\)
\(x=\frac{1}{2}\)/ \(5x+\frac{3}{4}=-\frac{13}{4}\)
\(5x=-4\)
\(x=-\frac{4}{5}\)

\(\Rightarrow x=\left\{\frac{1}{2};-\frac{4}{5}\right\}\)

b/\(\frac{3}{2}-\left|\frac{1}{2}x+1\right|=\frac{1}{4}\)

\(\left|\frac{1}{2}x+1\right|=\frac{5}{4}\)

1/\(\frac{1}{2}x+1=\frac{5}{4}\)
\(\frac{1}{2}x=\frac{1}{4}\)
\(x=\frac{1}{2}\)

2/\(\frac{1}{2}x+1=-\frac{5}{4}\)

\(\frac{1}{2}x=-\frac{9}{4}\)

\(x=-\frac{9}{2}\)​

\(\Rightarrow x=\left\{\frac{1}{2};-\frac{9}{2}\right\}\)