please please help marking brainlist but if you dont know than dont answer please thank you

Answer:
1. z = 5, 2. w = 9
Step-by-step explanation:
1. 5z - 4 = 21
5z = 21 + 4
5z = 25
z = 25/5
z = 5
2. w/9 + 2 = 3
w/9 = 3 - 2
w/9 = 1
w = 1 x 9
w = 9
I hope this helps :)