Answer:
12
Step-by-step explanation
PEMDAS is key to solving. First you multiply 4*5 because its the first parenthesis we see, to get 20. Next we see that 1-2 is in a different parenthesis, so we get -2. So our current equation is 20-10-2-1+5. You just add/subtract in that order. 20-10=10 10-2=8 8-1=7 7+5=12 So your final answer is 12.
