Simplify the left hand side by multiplying the terms in the parenthesis by 3/4, i.e. divide them by 4 and multiply them by 3:

Subtract 6x from both sides:

Subtract 2 to both sides:

You just need to plug those expressions inside the formula: it doesn't matter if they're expressions involving a variable instead of plain numbers: the formula becomes

If you want, you can simplify it by expanding the square and then multiply the two parenthesis:

I believe it might be 107.9 after if that’s what your asking-like taking off 10% of $108.