Answer:
area = 202.5 yd²
Step-by-step explanation:
area = (15 x 12 ) + (3)(15)(0.5)
area = 180 + 22.5 = 202.5 yd²
Answer:
-25-5x-5y
Step-by-step explanation:
Let x=balloon swords
let x+4=balloon dogs (four more than x is x+4)
let x+7=balloon hats (three more than x+4 is x+7)
the answer is x+7
I don't know how to correctly explain the second answer (although I do know that it is 1)
Answer:

Step By Step Explanation:
Simplify 

Rewrite Equation

Simplify 

I'm assuming that you are talking about sequences <3
In the context of a recursive formula where we have "n-1" in sub-index of "a", you can think of "a" as the previous term in the sequence. In the context of an explicit formula like "-5+2(n-1)" "n-1" represents how many times we need to add 2 to the first term to get the nth term.
Dw if you don't understand, sequences and functions isn't an easy topic