Question 530053
Basically I don't think this is an equation

6[6+9(25)]=1386 ---Don't be too hurry to remove the square bracket
6[6+225]=1386 ---After removing the parentheses, first calculate.
6[231]=1386 ---Then remove the square bracket
1386=1386 ---Congratulations! You completed a simple mathemactics problem in algebraic way :P