Well to find the volume of the square prism, first you need to multiply the base area (36) by its height (3) and you would end up with 108m3 as the volume. You may not be familiar with this because u are most likely taught length times width times height as volume, but what i just did is the same because length times width is the sum of the base area, and height was already given. Anyways, now that we have gotten the square prism volume (108m3) we need to find which prism has the same volume. I’m gonna save u from searching and tell you that it is the rectangular prism because length times width times height (18x2x3) equaled 108 just like the square prism.
And we are given that 
and want to find the value of x. Set f(x) to 16 and we get the equation:
Subtract both sides by 4
Divide both sides by 2
This is the answer. Let me know if you need any clarifications, thanks!
Regular Pirce = $80.
Discount = 20%
Discount = 20% x $80 = 0.2 x 80 = $16
Sale Price = 80 - 16 = $64
----------------------------------------------------
Answer: The Sale Price is $64.
----------------------------------------------------
T=2n+3
considering n has no other values given
