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.
Yes you always do.
eg x - 2 = 8
x - 2 + 2 = 8 + 2
x = 10
if we plug x = 10 into the original equation we se that this fits:-
10 - 2 = 8
Answer:
3/2
Sorry for the bad handwriting.