Answer:
A. add 81; 
Step-by-step explanation:
The perfect square formula

Rewrite expression
as follows:

So, to form a perfect square,
is missed.
When we add
we will get

Answer: CONFUSED LIKE REALLY CONFUSED BUT THANKS
Step-by-step explanation:
Answer:
30+(2x+7)+63=180(sum of angles of triangle )
30+2x+7+63=180
2x+100=180
2x=180-100
x=80/2
x=40
To move the function to the left you have to increase x inside the function
think of it like g(x)=f(x+7)
the solution is
y=(x+7)^2
Answer:
The study is an observational study.
Step-by-step explanation:
Observational study: In research methods, the term "observational study" is determined as one of the different studies that are being conducted by the researchers to observe or study the effects of a specific risk factor, treatment, diagnostic test, or some other intervention in the absence of an effort to change which participants are being exposed and which is not being exposed to it.
Types: Cohort study and case-control study.
In the question above, the given statement represents the observational study.