What is the value of a - b ? (1) a^2 - b^2 = 9 (2) a^2 - 2ab + b^2 = 1

Question

What is the value of (a - b) ?

(1)  a^2 - b^2=9

(2)  a^2-2ab+b^2=1

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chetan2u · Answer

What is the value of (a - b) ?

(1)  a^2 - b^2=9 
(a-b)(a+b)=9... a-b could be anything 1,9,1/9,-1,

(2)  a^2-2ab+b^2=1.......(a-b)^2=1......a-b=1..or ..a-b=-1

Combined 
a-b=1...a+b=9
a-b=-1..a+b=-9
Insufficient

E

Note a and b could be anything — positive or negative, integer or fraction

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