Đáp án:
Giải thích các bước giải:
a)-4(x+1)+8(9x-3)=24
-4x - 4 + 72x - 24 = 24
68x = 24 + 24 +4
68x = 4
x = $\dfrac{2}{49}$
vậy x=$\dfrac{2}{49}$
b) 4,5 - $\dfrac{3}{4}$ | $\dfrac{1}{2}$x + $\dfrac{5}{3}$ | =$\dfrac{5}{6}$
$\dfrac{3}{4}$ | $\dfrac{1}{2}$x + $\dfrac{5}{3}$ | = 4,5 - $\dfrac{5}{6}$
$\dfrac{3}{4}$ | $\dfrac{1}{2}$x + $\dfrac{5}{3}$ | = $\dfrac{11}{3}$
| $\dfrac{1}{2}$x + $\dfrac{5}{3}$ | = $\dfrac{11}{3}$ : $\dfrac{3}{4}$
| $\dfrac{1}{2}$x + $\dfrac{5}{3}$ | = $\dfrac{44}{9}$
$\dfrac{1}{2}$x + $\dfrac{5}{3}$ = ± $\dfrac{44}{9}$
trường hợp 1
$\dfrac{1}{2}$x + $\dfrac{5}{3}$ = $\dfrac{44}{9}$
$\dfrac{1}{2}$x = $\dfrac{44}{9}$ - $\dfrac{5}{3}$
$\dfrac{1}{2}$x = $\dfrac{29}{9}$
x = $\dfrac{29}{9}$ : $\dfrac{1}{2}$
x = $\dfrac{58}{9}$
trường hợp 2
$\dfrac{1}{2}$x + $\dfrac{5}{3}$ = $\dfrac{-44}{9}$
$\dfrac{1}{2}$x = $\dfrac{-44}{9}$ - $\dfrac{5}{3}$
$\dfrac{1}{2}$x = $\dfrac{-59}{9}$
x = $\dfrac{-118}{9}$
vậy x= $\dfrac{58}{9}$ hoặc x= $\dfrac{-118}{9}$
