Two companies working together can clear a parcel of land in 9 hours. working alone, it would take company a 2 hours longer to clear the land than it would company b. how long would it take company b to clear the parcel of land alone?

17 days.

Step-by-step explanation:

Let the company B takes x hours to clear the parcel of land alone.

Now, company A takes 2 hours longer time to clear the parcel of land than company B.

Therefore, company A will take (x + 2) hours to do the same job alone.

Now, Company A in one hour does part of the job.

And Company B in one hour does part of the job.

So, working together for one hour they will do parts of the job.

Therefore, they will complete the job in hours.

Hence, {Given}

⇒ x² + 2x = 18x + 18

⇒ x² - 16x - 18 = 0

Applying the Sridhar Acharya's formula,  

{Neglecting the negative root as x can not be negative}

⇒ x = 17 days (Answer)