Final answer:
To simplify the given expression, distribute -4 into both sets of parentheses and combine like terms, resulting in the simplified expression 12z - 8.
Step-by-step explanation:
To simplify the expression −4(z−3)−4(5−4z), we distribute the -4 into each parenthesis:
- −4 × z = −4z
- −4 × (−3) = +12
- −4 × 5 = −20
- −4 × (−4z) = +16z
Combining all the terms, we get −4z + 12 − 20 + 16z.
Now, combine like terms (−4z and +16z):
- (−4z + 16z) = 12z
- (+12 − 20) = −8
Finally, add the results of the like terms to get the simplified expression:
12z − 8, which corresponds to option (b) 12z + 8.