Answer:
-20x-5
Explanation:
you have to first distribute,
3(-9x+1)-1(-7x+8)
-27x+3-1(-7x+8)
-27x+3-1(-7x+8)
-27x+3+7x-8
now you have to subtract the numbers.
-27x+3+7x-8
-27x-5+7x
now you have to combine like terms,
-27x-5+7x
-20x-5
and thats how you get your answer.
hope this helps you. :)