Answer:

Explanation:
All that we have to do is add the 3 and 5 so it's basically like combining like terms. So the first blank is 8.
Now we add the x and the 5x which is 6x, all we're doing is adding the x's.
Now we do add the two negative 10 and 7. So what is -10 + - 7 we add them normally but we'll still have the negative in front of them. So it's -17.