A = side^2 * (2 + 2sqrt2))
A = 4^2 * (2 + 2sqrt2))
A = 77.25 cm^2
To do this you first have to set this up vertically.
First you multiply through with the 2 (44×2=88). Then next, you have to multiply through with the 1 (44×1=44) But since this is the second line, you have to add the 0 to the end (440).
Now you simply add 88+440=528.
Answer: Tammy's sample may not be vaild because she surveyed the students only from her class and it is likely that other classes might not like the subject maths. She might get the accurate results by surveying a larger number of people in the school instead of just her class.