Answer:
The value of n = 4 and
The value of x = 
Step-by-step explanation:
Method I:
As given, 12x -20=n (3x-5) .........(1)
Firstly , take 12x - 20
As 12x - 20 can be written as 4(3x - 5)
∴ equation (1) becomes
4(3x - 5) = n (3x-5)
Divide the equation by (3x-5) , we get
4 = n
Method II:
As given, 12x -20=n (3x-5)
⇒12x - 20 = 3nx - 5n
⇒12x - 3nx = 20 - 5n
⇒3x(4 - n) = 5( 4 - n)
Divide the equation by (4-n) , we get
3x = 5
⇒ x = 
∴ we get
n = 4 and x = 
Now, check that value of n and x satisfies the equation or not
12(
) - 20 = 4( 3(
) - 5)
⇒4(5) - 20 = 4(5 - 5)
⇒20 - 20 = 4(0)
⇒ 0 = 0
Hence , we get
The values of x and n satisfies the equation
so, we get
n = 4 and x = 