Answer:
z = 0
Step-by-step explanation:
3 (z + 7) = 21
3z + 21 = 21
3z = 0
z = 0
No, probably is on a scale between 0 and 1. Anything beyond those numbers is mathematically impossible. Since 3/2 = 1.5, it is not valid
It would be negative 5 since it is going down.
Combine like terms
-7y² + 6y² - 2y² = -3y²
4y + (-5y) - (-9y) = 4y - 5y + 9y = 8y
9 + 9 - (-2) = 9 + 9 + 2 = 20
-3y² + 8y + 20 is your answer
hope this helps