hi <3
this is a lot simpler if you just ignore the variable (basically the letter)
now you have -10 - 1
which gives you -11
now just add back on the variable to give you your answer of:
-11x
hope this helps :)
Answer
((10+9)x3-1)x2
=(19x3-1)x2
=(57-1)x2
=56x2=112