Factorise $9x(x-3) - 6(x-3)$.

Factorise $9x(x-3) - 6(x-3)$.
  1. $3(x-3)(3x-2)$
  2. $3(x-3)(3x+2)$
  3. $(x-3)(9x-6)$
  4. $9(x-3)(x-2)$

Solution

Take $3(x-3)$ common: $3(x-3)(3x-2)$. (Numerical GCD of 9 and 6 is 3, and $(x-3)$ is the binomial GCD.)

Asked in: IMO

Practice more FACTORISATION questions on Aicharya