Question

Giúp mk với các bạn. Trình bày chi tiết giúp mk nhá !

a) \(\left(\dfrac{1}{4}x-1\right)+\left(\dfrac{2}{3}x-2\right)-\left(\dfrac{5}{8}x+1\right)=5\)

b) \(2x-10-\text{[}3x-13-\left(3-5x\right)-4\text{]}=7\)

c)\(\left(\left|2x-1\right|-3\right).\left(-2\right)+\left(-5\right)=6\)

Answer 1

a: \(\Leftrightarrow\dfrac{1}{4}x-1+\dfrac{2}{3}x-2-\dfrac{5}{8}x-1=5\)

\(\Leftrightarrow x\cdot\dfrac{7}{24}-4=5\)

\(\Leftrightarrow x\cdot\dfrac{7}{24}=9\)

hay x=216/7

b: \(\Leftrightarrow2x-10-\left[3x-13-3+5x-4\right]=7\)

\(\Leftrightarrow2x-10-\left(8x-20\right)=7\)

=>2x-10-8x+20=7

=>-6x+10=7

=>-6x=-3

hay x=1/2

c: \(\Leftrightarrow\left(\left|2x-1\right|-3\right)\cdot\left(-2\right)=6+5=11\)

\(\Leftrightarrow\left|2x-1\right|-3=-\dfrac{11}{2}\)

=>|2x-1|=-5/2(vô lý)