a) $\dfrac{3}{4}$ + $\dfrac{1}{4}$x=0,2
$\dfrac{1}{4}$x=$\dfrac{1}{5}$ - $\dfrac{3}{4}$
$\dfrac{1}{4}$x=$\dfrac{-11}{20}$
x=$\dfrac{-11}{20}$ : $\dfrac{1}{4}$
x=$\dfrac{-11}{5}$.
b) 1-|x-$\dfrac{1}{2}$ - $\dfrac{1}{3}$ |=$\dfrac{1}{4}$
|x-$\dfrac{1}{2}$ - $\dfrac{1}{3}$ |=1-$\dfrac{1}{4}$
|x-$\dfrac{1}{2}$ - $\dfrac{1}{3}$ |=$\dfrac{3}{4}$
+,
x-$\dfrac{1}{2}$ - $\dfrac{1}{3}$ =$\dfrac{3}{4}$
x-$\dfrac{1}{2}$ =$\dfrac{3}{4}$ + $\dfrac{1}{3}$
x-$\dfrac{1}{2}$ =$\dfrac{13}{12}$
x=$\dfrac{13}{12}$+$\dfrac{1}{2}$
x=$\dfrac{19}{12}$
+,
x-$\dfrac{1}{2}$ - $\dfrac{1}{3}$ =-$\dfrac{3}{4}$
x-$\dfrac{1}{2}$ =-$\dfrac{3}{4}$ + $\dfrac{1}{3}$
x-$\dfrac{1}{2}$ =-$\dfrac{5}{12}$
x=-$\dfrac{5}{12}$+$\dfrac{1}{2}$
x=$\dfrac{1}{12}$.
c) $\dfrac{x+5}{4}$ = $\dfrac{x-3}{5}$
Ta có:
(x+5).5=(x-3).4
5x+25=4x-12
5x+4x=12+25
9x=37
x=$\dfrac{37}{9}$
Xin hay nhất! No coppy!
