Question

1. solve the following quadratic equation by factorisation method 81z - 16 = 0​

Answer 1

Answer:

u can write 81z^2 as (9z)^2 and 16 as 4 square

then use identity a^2-b^2=(a-b)(a+b)

Answer 2

Answer:

81z² - 16 = 0

(9z)² - 4² = 0

(9z+4) (9z-4) = 0