Question

suppose a+b=2a. which one of these expressions equals b-a?
A. 2b
B. 2a
C. 0
D. a/b
E. -2b

Answer 1

If a + b = 2a, then

a + b - 2a = 2a - 2a
b + a - 2a = 2a - 2a
b - a = 2a - 2a = 0

Therefore, b - a = 0.

Answer 2

ANSWER

C.
$0$

EXPLANATION

The given equation is

$a + b = 2a$

We make b the subject to get,

$b = 2a - a$

This simplifies to,

$b = a$

Subtracting
$a$
from both sides will give us,

$b - a = a - a$


The right hand side will now simplify to zero,

Therefore

$b - a = 0$