1) 3x-7y=2
2) If you're solving for x, you want to isolate it, so move the -7y to the right:
3x = 7y + 2
3) Now, to get x by itself, you divide both sides by 3
3x/3 = (7y + 2)/3
4) You get:
x = 7/3y + 2/3
20x^4-39x^3-16x
Make sure to multiply all the terms by each other in the two parentheses
John n. of stamps = N
Johan n. of stamps = n = Johnathan n. of stamps
2n = 5N -11
3n = 7N -3
So with some pen and paper work we get to the final result which is
N=27
n=62