Factories z2−4z−12
Given: z2−4z−12
We have to find two numbers such that their product is −12z2 and their sum is −4z.
Such two numbers are −6z and 2z.
Using Middle Term Splitting,
⇒z2−6z+2z−12
⇒z(z−6)+2(z−6)
⇒(z−6)(z+2)
∴z2−4z−12=(z−6)(z+2)
Hence, the given expression has been factorised.