Question

Suppose a - b = 0 which expression equals a + b?

a. o
b. -2b
c. -b^2
d. a/b
e. 2a

Answer 1

Hello from MrBillDoesMath!

Answer:

Choice e (2a)

Discussion:

a - b = 0 => a = b (*)

So

a + b = (b) + a => commutative property and b = a from (*)

= (a) + a

= 2a

which is Choice e.

Thank you,

MrB