Answer:
first is 20 second is 40 third is 60 and last is 80
Step-by-step explanation:
A perfect square is something times that same thing. Example (x+2)(x+2)
The reason it's called a perfect square is because it can be re-written as a squared function:
1. It's a proportion...50 over 12.5 = h over 50 then cross multiply and divide
2. Another proportion 7over x = 2 over 6 then cross multiply and divide