Question

Which expression is equivalent to 0?
(a)(-a)
a +(-a)
a/-a
a - (-a)

Answer 1

a+(-a) equals zero because they cancel each other out .

(a)(-a) equals -a
a/-a equals -a
and
a-(-a) equals positive a

Answer 2

a - a or (a +(-a))

Explanation:

A negative plus a positive is always zero if they have the same variable.