Phytagorean Theorem i think
If c = the cost of one table, the cost of all 25 tables before sales tax is 25·c
Since the sales tax is 5%, or 0.05, the sales tax for 25 tables is 25·c·0.05
Adding the sales tax to the original cost of the 25 tables can give you:
25·c + 25·c·0.05 = 1706.25
1.05·25·c = 1706.25
26.25·c = 1706.25
c =

= 65
so the refund for 5 tables would be 5*65 = $325
Add sin(x) to both sides
tan(x)sin(x)=sin(x)
Divide sin(x) from both sides
tan(x)=1
now you just have to figure out where tan(x)=1. you can figure this out from there by looking at the unit circle.
Aritmetic increases by the same number
geometric has 1 number that each term is multiplied by to get the next term
4 to 9 is 5
9 to 13 is 4
not same difference
9/4=13/9?
81/36=52/36?
no
neither aritmetic nor geometric