Since 2+4^2 is 16+2 which is 18, you need to find the expression equivalent to 18. 25 doesn't work so eliminate that right away. 9^2=81 so that isn't right either. 2^3+9=17 so that is incorrect. Lastly, 3^2+9=18 so that is the correct answer.
Since 2+(4^2)=18 all you have to do is find an equation that equals 18, and the equation available is (3^2)+9=18, it makes both equations equal to each other and they both equal 18
