Answer:
7z³ + 6z² - 27z + 22
Explanation:
It is given an expression in variable z,
(7z³ + 42z² - 15z + 1) - (36z² + 12z - 21)
To find the simplified form
(7z³ + 42z² - 15z + 1) - (36z² + 12z - 21)
= (7z³ + 42z² - 15z + 1 - 36z² - 12z + 21)
= 7z³ + 42z² - 36z² - 15z -12z + 1 + 21
= 7z³ + 6z² - 27z + 22
Therefore the simplified expression is = 7z³ + 6z² - 27z + 22