đề là tìm x hả ??

Đây là những bài cơ bản mà bạn!

\(\frac{5x-2}{3}=\frac{5-3x}{2}\)

\(< =>\frac{\left(5x-2\right).2}{6}=\frac{\left(5-3x\right).3}{6}\)

\(< =>\left(5x-2\right).2=\left(5-3x\right).3\)

\(< =>10x-4=15-9x\)

\(< =>10x+9x=15+4\)

\(< =>19x=19< =>x=1\)

\(\frac{10x+3}{12}=1+\frac{6+8x}{9}\)

\(< =>\frac{\left(10x+3\right).3}{36}=\frac{36}{36}+\frac{\left(6+8x\right).4}{36}\)

\(< =>\left(10x+3\right).3=36+\left(6+8x\right).4\)

\(< =>30x+9=36+24+32x\)

\(< =>32x-30x=9-36-24\)

\(< =>2x=9-60=-51< =>x=-\frac{51}{2}\)

\(b,\frac{2x-\frac{4-3x}{5}}{15}=\frac{7x-\frac{x-3}{2}}{5}-x+1\)

\(\Leftrightarrow\frac{2x}{15}-\frac{4-3x}{75}=\frac{7x}{5}-\frac{x-3}{10}-x+1\)

\(\Leftrightarrow\frac{10.2x}{150}-\frac{2\left(4-3x\right)}{150}=\frac{30.7x}{150}-\frac{15\left(x-3\right)}{150}-\frac{150\left(x-1\right)}{150}\)

\(\Leftrightarrow2x-8+6x=210x-15x+45-150x+150\)

\(\Leftrightarrow-19x=203\)

\(\Leftrightarrow x=-\frac{203}{19}\)

Vậy ............

\(\frac{5x-1}{10}+\frac{2x+3}{6}=\frac{x-8}{15}-\frac{x}{30}\)

\(\Rightarrow\frac{3\left(5x-1\right)}{30}+\frac{5\left(2x+3\right)}{30}=\frac{2\left(x-8\right)}{30}-\frac{x}{30}\)

\(\Rightarrow15x-3+10x+15=2x-16-x\)

\(\Rightarrow24x=-28\)

\(\Rightarrow x=-\frac{7}{6}\)

* \(\frac{2x+\frac{3x-4}{5}}{15}=\frac{\frac{10x+3x-4}{5}}{15}=\frac{13x-4}{5}.\frac{1}{15}=\frac{13x-4}{75}\)

*\(\frac{\frac{3-x}{2}+7x}{5}=\frac{\frac{3-x+14x}{2}}{5}=\frac{\frac{3+13x}{2}}{5}=\left(\frac{3+13x}{2}.\frac{1}{5}\right)=\frac{3+13x}{10}\)

➝\(\frac{\frac{3-x}{2}+7x}{5}+1-x=\frac{3+13x}{10}+1-x=\frac{3+13x+10\left(1-x\right)}{10}=\frac{13+3x}{10}\)BPT⇔\(\frac{13x-4}{75}< \frac{13+3x}{10}\)

⇔\(\frac{13x}{75}+\frac{3x}{10}< \frac{13}{10}+\frac{4}{75}\)

⇔\(\frac{-19x}{150}< \frac{203}{150}\)

⇔\(x>\frac{-203}{19}\approx-10.68\)

a) \(\frac{6x-5}{-7}=\frac{5x-3}{-5}\)

=> -5(6x - 5) = -7(5x - 3)

=> -30x + 25 = -35x + 21

=> -30x + 25  + 35x - 21 = 0

=> (-30x + 35x) + (25 - 21) = 0

=> 5x + 4 = 0

=> 5x = -4

=> x = -4/5

b) \(\frac{12-7x}{-13}=\frac{4-3x}{-5}\)

=> -5(12 - 7x) = -13(4 - 3x)

=> -60 + 35x = -52 + 39x

=> -60 + 35x + 52 - 39x = 0

=> (-60 + 52) + (35x - 39x) = 0

=> -8 - 4x = 0

=> -8 = 4x

=> x = -2

c) \(\frac{2x+4}{7}=\frac{4x-2}{15}\)

=> 15(2x + 4) = 7(4x - 2)

=> 30x + 60 = 28x - 14

=> 30x + 60 - 28x + 14 = 0

=> 2x + 74 = 0

=> 2x = -74

=> x = -37

\(\frac{9x-0,7}{4}-\frac{5x-1,5}{7}=\frac{7x-1,1}{6}-\frac{5\left(0,4-2x\right)}{6}\)

\(\Leftrightarrow\frac{\left(9x-0,7\right)\cdot7}{4\cdot7}-\frac{\left(5x-1,5\right)\cdot4}{7\cdot4}=\frac{7x-1,1-2+10x}{6}\)

\(\Leftrightarrow\frac{63x-4,9-20x+6}{28}=\frac{7x-1,1-2+10x}{6}\)

\(\Leftrightarrow\left(63x-4,9-20x+6\right)\cdot6=28\left(7x-1,1-2+10x\right)\)

\(\Leftrightarrow378x-120x+6,6=196x-86,8+280x\)

\(\Leftrightarrow378x-120x-196x-280x=-86,8-6,6\)

\(\Leftrightarrow-218x=-93,4\)

\(\Leftrightarrow x=\frac{467}{1090}\)