Question

Which of the following must be true for an expression to be a difference of two squares?

a. all variables are raised to an even power
b. there are only two terms
c. both terms have negative coefficients

A. a, b, and c
B. b and c
C. a and b
D. a and c

Answer 1

so let us take an expression(e) which is a difference of two squares.
\[e=a ^{2}-b ^{2}\]
so here a and b are 2 variables.
A:2 is even, so both the variable are raised to even power.
B: There are only two terms because it's a difference of two squares.
C: both terms may or may not have -ve coefficients because square of -ve as well as a +ve number is always +ve.

Answer 2

so a and b are true but we can not say that c must be true because it's partially true.

Answer 3

So would it be C?

Answer 4

yup

Answer 5

Thank you so much!

Answer 6

you're welcome...:)