3×3-3-3=3(3×3+3)÷3=4(3+3)÷3+3=53+3+3-3=63+3+3÷3=7
3X3-3-3=3(3+3X3)/3=43+3-3/3=53+3+3-3=63+3+3/3=7
3×3-(3+3)=3(3+3×3)÷3=43+(3+3)÷3=53-3+3+3=63+3÷3+3=7
3×3-3-3=3(3+3×3)÷3=43+(3+3)÷3=53+3+3-3=63÷3+3+3=7
× - -× + ÷+ ÷ ++ + -÷ + +