Find the difference. (-ab+8a-5) - (-8ab-4)

(-a) (b) + 8a - 5 - (( - 8a) (b) - 4)

So first

Distribute the Negative Sign:

= (-a) (b) + 8a - 5 + - 1 (( - 8a) (b) - 4)

= (-a) (b) + 8a + - 5 + - 1 (( - 8a) (b)) + (-1) (-4)

= (-a) (b) + 8a + - 5 + 8a b + 4 = - ab + 8a + - 5 + 8a b + 4

Then after all of that

Combine Like Terms: = - ab + 8a + - 5 + 8a b + 4

= ( - ab + 8a b) + (8a) + (-5 + 4)

So now your answer is = 7a b + 8a + - 1

-ab + 8a - 5 - (-8ab - 4) =

-ab + 8a - 5 + 8ab + 4 =

8a + 7ab - 1 <===