How do you find the concentration of an acid if 35.0 mL of 0.20 M NaOH is required to neutralize 45.0 mL of HCL. Do you know how I would calculate this?

mols NaOH = M x L = ?

mols HCl = mols NaOH (from the coefficients in the balanced equation)
M HCl = mols HCl/L HCl.