Answer: 20
When they say evaluate an expression they usually mean replace the variable with the values they've given.
Replacing in the question,
4+(10-7)^2 *2
According to PEMDAS, we will evaluate the parenthesis first.
4+3^2 *2
=>4+9*2
Now we will multiply(again according to PEMDAS),
=>2+18
=>20
There you go! Good luck with mathematics :)