#### Answer

z = -6

#### Work Step by Step

5(3 + z) - (8z + 9) = -4z
Apply distributive property:
5(3) + 5(z) - 8z - 9 = -4z
15 + 5z - 8z - 9 = -4z
Combine like terms:
-3z + 6 = -4z
Add 4z to both sides:
z + 6 = 0
Subtract 6 from both sides:
z = -6
Check with substitution:
5(3 + (-6)) - (8(-6) + 9) = -4(-6)
5(-3) - (-48 + 9) = 24
-15 - (-39) = 24
24 = 24