Question

\(d,\left|x-\frac{2}{5}\right|+\frac{1}{2}=\frac{3}{4}\)

e,\(\frac{5}{6}-\left|2-x\right|=\frac{1}{3}\)

g,\(-2,5+\left|3x+5\right|=-1,25\)

 

Answer 1

d. \(\left|x-\frac{2}{5}\right|+\frac{1}{2}=\frac{3}{4}\)

             \(\left|x-\frac{2}{5}\right|=\frac{3}{4}-\frac{1}{2}\)

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

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

Vậy \(x-\frac{2}{5}=\frac{1}{4}\) hoặc \(x-\frac{2}{5}=\frac{-1}{4}\)

* \(x-\frac{2}{5}=\frac{1}{4}\)

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

            \(x=\frac{5+8}{20}\)

            \(x=\frac{13}{20}\)

 

* \(x-\frac{2}{5}=\frac{-1}{4}\)

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

            \(x=\frac{-5+8}{20}\)

            \(x=\frac{3}{20}\)

Vậy \(x\in\left\{\frac{13}{20};\frac{3}{20}\right\}\)

Answer 2

d) |x-2/5| +1/2 = 3/4

=> |x-2/5| = 1/4

<=> x-2/5 = 1/4 hoặc x=2/5 = -1/4

<=> x=13/20 hoặc 3/20

e) 5/6 -| 2-x| = 1/3

=> |2-x|=1/2

<=> 2-x=1/2 hoặc 2-x=-1/2

<=> x=3/2 hoặc x=5/2

g) làm tương tự

 

Answer 3

d, / x-2/5 / =3/4+1/2

=>/ x-2/5 /=5/4

=>x-2/5 = 5/4 hoặc x-2/5=-5/4

+) Với x-2/5=5/4=>x=8/5

+) Với x-2/5=-5/4=>x=-17/20

vậy x=8/5; x=-17/20

          e, 5/6 -/2-x/=1/3

            =>/2-x/ = 1/2 

            => 2-x=1/2 ; 2-x=-1/2

+) 2-x=1/2=> x=3/2

+) 2-x=-1/2=> x=5/2

vậy x=3/2; x=5/2

             g, -2,5 + /3x+5/ = 1,25

              =>   /3x+5/  = 3,75

              => 3x+5 =3,75 ;  3x+5=-3,75

+) Với 3x+5 =3,75 => x=-5/12

 +) Với 3x+5 =-3,75 => x=-35/12

vậy x=-5/12 ; x=-35/12