100÷10-[-2+{-9+(3-6 of 2)}]= 

​100÷10-[-2+{-9+(3-6 of 2)}] 

Simplification using BODMAS rule; 

​$$\begin{array}{|c|c|} \hline \textbf{Operation preference wise} & \textbf{Symbol} \\ \hline Brackets &[],{}, () \\ \hline Orders, of & ² (power), √ (root) , of \\ \hline Division & ÷ \\ \hline Multiplication & × \\ \hline Addition & + \\ \hline Subtraction & - \\ \hline \end{array}$$​​

$$100 \div 10 - [ -2+ \{ -9 +(3 - 6 \text { of} \ 2) \} ]$$ 

$$\begin{aligned}& 10 - [ -2+ \{ -9 +( -9) \} ] \\&10 -[ -2 - 18] \\&10 - [ -20]\\&10+20 \\&30\end{aligned}$$​​

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