If a2 + b2 =13, what is the value of ab? (just to clarify, the 2s are squares)
(1) (a + b)2 = 25 (just to clarify, the 2 after a+b is square)
(2) a(ab3) = 108 (just to clarify, the 3 is cube)
Statement (1) ALONE is sufficient, but statement (2) ALONE is not sufficient.
Statement (2) ALONE is sufficient, but statement (1) ALONE is not sufficient.
BOTH statements TOGETHER are sufficient, but NEITHER statement ALONE is sufficient.
EACH statement ALONE is sufficient.
Statements (1) and (2) TOGETHER are NOT sufficient.
I got D since both can answer
But the test I took says the answer is A. Am I missing something? Doesn't B also help?
Please help.
DS Problem
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Statement 1 => a2 +2ab +b2 = 25 ; Given in the question that a2 +b2 =13 so we can find value of abjitsy wrote:If a2 + b2 =13, what is the value of ab? (just to clarify, the 2s are squares)
(1) (a + b)2 = 25 (just to clarify, the 2 after a+b is square)
(2) a(ab3) = 108 (just to clarify, the 3 is cube)
Please help.
Statement 2 => a2b3 = 2^2 . 3^3 which means a =2 ; b =3 OR a=-2 or b=3; so Stmt 2 insufficient