Answer:
z = 7
Step-by-step explanation:
4z - 8 = 20
Add 8 to each side
4z - 8+8 = 20+8
4z = 28
Divide each side by 4
4z/4 = 28/4
If you add 690 ml of water you will obtain 1.690 liter of 70% alcohol. Of course if you halve the amounts, e.g. 0.5 liter 75% alcohol and 345 ml of water, you will also obtain 45% alcohol solution.
x^8
(x^4)^2
~Apply power rule [ (a^b)^c = a^bc ]
x^4(2)
~Simplify
Best of Luck!
