14 more than 5 times a number is equal to 20. find the number

Ican figure out 20 shares multiply by $117.98 =2359.6920 shares multiply by $124.32=2486.40then take 40 shares multiply by $128.48=5139.20after that i'm lost any be greatly appreciated.

What’s the domain of this function? fastttt

The graph represents the gallons of water in a water tank with respect to the number of hours since it was completely filled