Answer:
39
Step-by-step explanation:
I'm assuming x is supposed to be a multiplication sign.
You need to use PEMDAS for this:
Parentheses
Exponents
Multiplication
Division
Addition
Subtraction
(9x2+3x-5)-(3x2+4x-10)=
(18-15)-(6-40)=
3-(-36)=
3+36=
39
