`a, x+2/9=1 1/2 -7/9`
`=>x=3/2 - 7/9-2/9`
`=>x=3/2-1`
`=>x=1/2`
Vậy: `x=1/2`
`b, -13/15 + x = (-3)/8 - (-4)/5`
`=> -13/15 + x = -3/8 + 4/5`
`=> -13/15 + x = 17/40`
`=> x = 17/40 + 13/15`
`=> x = 31/24`
Vậy: `x = 31/24`
`c, (-8)/13 + ((-7)/5 - x) = (-1)/2`
`=> -7/5 - x = (-1)/2 + 8/13`
`=> -7/5 - x = 3/26`
`=> x = -7/5 - 3/26`
`=>x = -197/130`
Vậy: `x = -197/130`
`d, (-3)/11 - (x - 2/5) = (-14)/22`
`=> (-3)/11 - (x -2 /5) = -7/11`
`=> x - 2/5 = -3/11 + 7/11`
`=> x - 2/5 = 4/11`
`=> x = 4/11 + 2/5`
`=> x = 42/55`
Vậy: `x = 42/55`
`e, 3/20 - x = (-4)/5 + 1/10`
`=> 3/20 - x = -7/10`
`=> x = 3/20 + 7/10`
`=> x = 17/20`
Vậy: `x = 17/20`
`f, (x+2)^2=25`
`=> (x+2)^2 = (+-5)^2`
`=> [(x+2=5),(x+2=-5):}`
`=> [(x=3),(x=-7):}`
Vậy: `x=3;x=-7`
`g, (2x-1)^3 - 27 = 0`
`=> (2x-1)^3=27`
`=>(2x-1)^3=3^3`
`=>2x-1=3`
`=>2x=4`
`=>x=2`
Vậy: `x=2`
`h, (4x-9)(2,5+(-7/3)x) = 0`
`=> [(4x-9=0),(2,5+ (-7/3)x) = 0):}`
`=> [(4x = 9),(-7/3x = -5/2):}`
`=> [(x = 9/4),(x=15/14):}`
Vậy: `x=9/4;x=15/14`
