Answer:
z = 8
Explanation:
Solve for z: 
(z + 4)/3 - 6 = (2 (5 - z))/3 
 
Put each term in (z + 4)/3 - 6 over the common denominator 3: (z + 4)/3 - 6 = (z + 4)/3 - 18/3: 
(z + 4)/3 - 18/3 = (2 (5 - z))/3 
 
(z + 4)/3 - 18/3 = ((z + 4) - 18)/3: 
(z - 18 + 4)/3 = (2 (5 - z))/3 
 
Add like terms. 4 - 18 = -14: 
(z - 14)/3 = (2 (5 - z))/3 
 
Multiply both sides by 3: 
(3 (z - 14))/3 = (3×2 (5 - z))/3 
 
(3 (z - 14))/3 = 3/3×(z - 14) = z - 14: 
z - 14 = (3×2 (5 - z))/3 
 
(3×2 (5 - z))/3 = 3/3×2 (5 - z) = 2 (5 - z): 
z - 14 = 2 (5 - z) 
 
Expand out terms of the right hand side: 
z - 14 = 10 - 2 z 
 
Add 2 z to both sides: 
2 z + z - 14 = (2 z - 2 z) + 10 
 
2 z - 2 z = 0: 
2 z + z - 14 = 10 
 
z + 2 z = 3 z: 
3 z - 14 = 10 
 
Add 14 to both sides: 
3 z + (14 - 14) = 14 + 10 
 
14 - 14 = 0: 
3 z = 10 + 14 
 
10 + 14 = 24: 
3 z = 24 
 
Divide both sides of 3 z = 24 by 3: 
(3 z)/3 = 24/3 
 
3/3 = 1: 
z = 24/3 
 
The gcd of 24 and 3 is 3, so 24/3 = (3×8)/(3×1) = 3/3×8 = 8:
Answer: z = 8