Answer:
a^2 + 2ab + b^2 - c^2
Step-by-step explanation:
When you multiply all the terms together you get a^2 + ab + ac + ab + b^2 + bc - ac - bc - c^2. Then you can just combine like terms and simplify it to a^2 + 2ab + b^2 - c^2. Hope this helps :)
So 20% is 1/5 as a percent.
So 1/5 multiplied by 5 equals 5/5, or 1.
So if 1/5 = 6, then 6 multiplied by 5, or 30, must equal 5/5, or 1.
So the total number of dolls in Amyia's doll collection is 30.