40÷{20-4×(7-4)]
First you need to solve what is in parentheses
40÷{20-4×3]
Do order of operations inside of absolute value bars, which is 4x3
40÷{20-12]
Solve inside of absolute value bars
40÷[8]
Simplify(8 remains positive)
40÷8
simplify
5
The final answer is 5
Hope this helped