B is the answer to the question :)

The difference is the result of a subtraction problem.
We are given two values that are being subtracted: 54 and a number, represented by 
So, represent this mathematically with
.
1.33333333333333333333333333333333333333333333333
or 1.33
3(1,000,000)=3,000,000
3(100,000)=300,000
2(100)=200
3,300,200
Hello :
<span>7x-2y=1 ...(1)
2y=x-1...(2)
</span><span>substitution 2y in (1) :
</span>7x-(x-1) = 1
7x-x+1 = 1
7x = 0
x=0
in (2) : 2y = 0-1
2y = -1 y= -1/2
the <span>system have one solution : (0 ;-1/2)</span>