Find the coefficient of the x4y2 term in the expansion of
(3x - y)
[ ? ]xy?

URGENT! Picture included

-540

Step-by-step explanation:

From binomial theorem, we can know

first term would be x^6

2nd term x^5

3rd term x^4

4th term x^3

Also, from binomial theorem, we can know

first term would be y^0

2nd term would be y^1

3rd term would be y^2

4th term would be y^3

We can see that we are looking for the 4th term (x^3y^3).

To find coefficient of 4th term, we use write:  

We can expand 6C3 using formula:    

Thus, the coefficient is -540

distance covered by pamela in 9 l of fuel = 99km

let us apply unitary method here.

distance covered by pamela in 1 l of fuel =99/9 =11 km

now let us find distance covered by pamela if she has 12 l of fuel.

distance covered in 12 l = distance covered in 1 l of fuel * 12

we know that distance covered by here in 1 l is 11 km.

so distance covered in 12 l of fuel = 11*12 = 132 km.