The equation is:
12.99 + 2.10b = 21.39
Subtract 12.99 from each side to get:
2.10b = 8.4
Then divide to find the amount of bottles:
b = 4 bottles
Hope this helps!! :)
<span>(-4-x)-(3y-9x)
= </span><span>-4 - x - 3y + 9x
= 8x - 3y - 4</span>
The solution to the two functions is (1, 3) and it represents the temperature at which the number of people visiting the zoo equals the number of people leaving the zoo.