If 3825=3^x × 5^y × 17^z, then the value of x + y -2 z is:

If $\displaystyle 3825=3^{\mathrm{x}} \times 5^{\mathrm{y}} \times 17^{\mathrm{z}}$, then the value of $\displaystyle \mathrm{x}+\mathrm{y}-2 \mathrm{z}$ is :