when subtracting a polynomial, do you subtract the variable as well?
ex. 8x2 - 6x = 2x
or is that wrong?
That's wrong
For your example, you can only do 2x(4x-3)
We can only add/subtract like terms [terms having variables to the same power]
Since 8x2 has a different exponent on x than 6x, we cannot add/subtract them