4)
2/3 (1/3 х -0,5 ) =4х+2,5
2/9 х - 1/3 = 4х +2,5
2/9 х - 4х= 2,5 + 1/3
- 3 7/9 х = 5/2 + 1/3
- 3 7/9 х = 15/6 + 2/6
- 34/9 х = 17/6
х= 17/6 : (-34/9) = 17/6 * (- 9/34 )= - (1*3)/ (2*2)
х= - 3/4
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2/3 ( 1/3 * (-3/4) -0,5 ) = 4/1 * (-3/4 )+2,5
2/3 ( - 1/4 - 1/2) = -3 +2,5
2/3 (- 1/4 -2/4 ) =-0,5
2/3 * (- 3/4 )=-0,5
- 1/2 =-0,5
- 0,5=-0,5
8)
0,75х - 1 2/3 = 1,5 +0,2х
0,75х -0,2х = 1 1/2 + 1 2/3
0,55х= 3/2 +5/3
0,55х= 9/6 +10/6
0,55х= 19/6
х= 19/6 : 55/100 = 19/6 * 20/11 = 190/33
х=5 25/33
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0,75 * 5 25/33 - 1 2/3 =1,5 + 0,2 * 5 25/33
3/4 * 190/33 - 1 2/3 = 1,5 + 1 5/33
95/22 - 5/3 = 3/2 + 38/33
2 43/66 = 2 43/66