Btw before I answer this, this is not an English question.
I am going to use PEMDAS:
Parenthesis first 1+2=3 so 24-4*3+9-7
No exponents
Multplication and division 4*3=12 so 24-12+9-7
Addition and subtraction 24-12=10, 10+19=19, 19-7=12
I hope this helps.
