You can put this solution on YOUR website! Parenthesis
Exponents
Multiplication/Division
Addition/Subtraction
4*5+9-2*(1+2)
Use parenthesis so that (1+2) = 3
4*5+9-2*3
Do multiplication:
20 + 9 - 6 since 4*5 =20 and 2*3 = 6
Finishing this up gives us 23.