Answer:35x^3 + 15x^2 + 42xz + 28x + 18z + 12
Step-by-step explanation:
(7x + 3) (5x^2 + 6z + 4)
7 (5^2 + 6 + 4) +3 (5^2 + 6 + 4)
35^3 +42 + 28 + 15^2 + 18 + 12
35^3 + 15x^2 + 42xz + 28x + 18z + 12
