`a)[3x-2]/4=5/2`
`=>2(3x-2)=20`
`=>3x-2=10`
`=>3x=12`
`=>x=4`
`b)(2x-1):4=28:16`
`=>(2x-1):4=7/4`
`=>2x-1=7/4.4`
`=>2x-1=7`
`=>x=4`
`c)[9x+3]/9=8/3`
`=>[3x+1]/3=8/3`
`=>3x+1=8`
`=>x=7/3`
`d)(6x-12):1,5=7:2,5`
`=>(6x-12):1,5=2,8`
`=>6x-12=4,2`
`=>x=2,7`
`a, (3x - 2)/4 = 5/2`
`=> (3x - 2) * 2 = 5 *4`
`=> 6x - 4 = 20`
`=> 6x = 24`
`=> x = 4`
Vậy: `x = 4`
`b, (2x - 1) : 4 = 28 : 16`
`=> (2x -1)/4 = 7/4`
`=> (2x - 1)*4 = 7*4`
`=> 8x - 4 = 28`
`=> 8x = 32`
`=> x = 4`
Vậy: `x=4`
`c, (9x + 3)/9 = 8/3`
`=> (9x + 3) *3 = 9*8`
`=> 27x + 9 = 72`
`=> 27x = 72 - 9`
`=> 27x = 63`
`=> x = 63 : 27`
`=> x = 7/3`
Vậy: `x=7/3`
`d, (6x - 12):1,5=7:2,5`
`=> (6x-12)/(1,5) = 7/(2,5)`
`=> (6x - 12) . 2,5 = 7 * 1,5`
`=> 15x - 30 = 10,5`
`=> 15x = 40,5`
`=> x=2,7`
Vậy: `x=2,7`
\(a,\dfrac{3x-2}{4}=\dfrac{5}{2}\)
\(\left(3x-2\right).2=5.4\)
\(\left(3x-2\right).2=20\)
\(3x-2=20:2\)
\(3x-2=10\)
\(3x=10+2\)
\(3x=12\)
\(x=12:3\)
\(x=4\)
Vậy \(x=4\)
\(b,\left(2x-1\right):4=28:16\)
\(\left(2x-1\right):4=\dfrac{7}{4}\)
\(\left(2x-1\right)=\dfrac{7}{4}.4\)
\(2x-1=7\)
\(2x=7+1\)
\(2x=8\)
\(x=8:2\)
\(x=4\)
Vậy \(x=4\)
\(c,\dfrac{9x+3}{9}=\dfrac{8}{3}\)
\(\left(9x+3\right).3=8.9\)
\(\left(9x+3\right).3=72\)
\(9x+3=72:3\)
\(9x+3=24\)
\(9x=24-3\)
\(9x=21\)
\(x=21:9\)
\(x=\dfrac{7}{3}\)
Vậy \(x=\dfrac{7}{3}\)
\(d,\left(6x-12\right):1,5=7:2,5\)
\(\left(6x-12\right):1,5=\dfrac{14}{5}\)
\(6x-12=\dfrac{14}{5}.1,5\)
\(6x-12=\dfrac{14}{5}.\dfrac{3}{2}\)
\(6x-12=\dfrac{7.3}{5.1}\)
\(6x-12=\dfrac{21}{5}\)
\(6x=\dfrac{21}{5}+12\)
\(6x=\dfrac{81}{5}\)
\(x=\dfrac{81}{5}:6\)
\(x=\dfrac{81}{5}.\dfrac{1}{6}\)
\(x=\dfrac{81}{30}\)
\(x=\dfrac{27}{10}\)
\(x=2,7\)
Vậy \(x=2,7\)