Verified answer

а) 2 · (2/5z + 1) + 3 1/3 = 4 - 1/2 · (4/5z - 1)

4/5z + 2 + 3 1/3 = 4 - 2/5z + 1/2

4/5z + 5 1/3 = 4 1/2 - 2/5z

4/5z + 2/5z = 4 1/2 - 5 1/3

6/5z = 4 3/6 - 5 2/6

6/5z = -5/6

z = -5/6 : 6/5

z = -5/6 · 5/6

z = -25/36

- - - - - - - - - - - - - - - - - - - -

б) 5 - (1 1/2v + 1/3) · 6 = 2 1/3v - 5 1/2

5 - (3/2v + 1/3) · 6 = 2 1/3v - 5 1/2

5 - 9v - 2 = 2 1/3v - 5 1/2

3 - 9v = 2 1/3v - 5 1/2

-9v - 2 1/3v = -5 1/2 - 3

-11 1/3v = -8 1/2

-34/3v = -17/2

v = -17/2 : (-34/3)

v = 17/2 · 3/34 = (1·3)/(2·2)

v = 3/4 (или 0,75 в десятичных дробях)