Value of (a+b)?
1- a^2+b^2=13
2- 2b=12/a
Answer: C ?
I think it shoud be E because we get to answer for a+b
could somebody help?
confusing DS!
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2b=12/arahi08 wrote:Value of (a+b)?
1- a^2+b^2=13
2- 2b=12/a
Answer: C ?
I think it shoud be E because we get to answer for a+b
could somebody help?
ab = 6
a^2+b^2=13
a^2 + b^2 + 2ab = 13+2ab
(a+b)^2 = 13+12
(a+b)^2 = 25
(a+b) = 5
Now here I am little confused about the whole thing
if
(a+b)^2 = 25
then,
a+b = -5
or
a+b = 5
Can someone pls guide me on this. This thing keeps troubling me for some or the other reason.
When to consider both + and - for squares.
Thanks.