Respuesta :

DatGuy323

This expression cannot be simplified, as you cannot add or subtract variables raised to different exponents.

devishri1977

Answer:

Step-by-step explanation:

6z⁶ - 21z⁴ - 12z² = 2*3*z⁶ - 3*7*z⁴ - 4*3*z²

                           = 3z² (2z⁴ - 7z² - 4)