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

A. 2t-7
Hope this helps! :)
SOLUTION:
A normal distribution would model this situation because the distribution is approximately symmetrical, thus the mean, median and mode are approximately the same and the population size is large ( greater than 30).
Hello!
To find the greatest common factor, you must find all the factors of both numbers and see which similar one is the greatest.
27: (1,27) (3,9)
36: (1,36) (2,18) (3,12) (4,9) (6,6)
As you can see the, the greatest common factor is 9.
I hope this helps!