Answer:
z = 351/10 or z = 35.1
Explanation:
*Add/subtract numbers: -49 + 851 = 802
z + 802 = 100 + 21z
*Subtract 802 from both sides
z + 802 - 802 = 100 + 21z - 802
*Simplify
z = 21z - 702
*Subtract 21z from both sides
z - 21z = 21z - 702 - 21z
*Simplify
-20z = -702
*Divide both sides by -20
- 20z/20 = - 702/- 20
*Simlify
z = 351/10 or z = 35.1