SOLUTION: if a and x represent real numbers for which x^2 = -a, which of the following statements could be true ? I a > 0 II a = 0 III a

SOLUTION: if a and x represent real numbers for which x^2 = -a, which of the following statements could be true ? I a > 0 II a = 0 III a < 0 (A)None (B

Question 295786: if a and x represent real numbers for which x^2 = -a, which of the following statements could be true ?
I a > 0
II a = 0
III a < 0

(A)None
(B)II only
(C)III only
(D)I and II only
(E)II and III only

Found 2 solutions by richwmiller, Deina:
Answer by richwmiller(17219) (Show Source): You can put this solution on YOUR website!
if a>0 then x^2=-a then x would be an imaginary number
so a is not greater than 0
if a-=0 then x=0 also
that is possible
if a<0 then the -a= is a positive number this could be
so (E) II and III only
Answer by Deina(147) (Show Source): You can put this solution on YOUR website!
Take what you know about squaring numbers and think it out.

A positive number squared = ?
A negative number squared = ?

Now, what result for a will make true?

Should take just a few seconds & bob's your uncle!

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