If sqrt{(x+4)^2} = 3, which of the following could be the value of x – 4?
-11
-7
-4
-3
5
oa is A
-----"MGMAT's solution:-
the expression can be simplified to |x + 4|, and the original equation can be solved accordingly.
If |x + 4| = 3, either x = -1 or x = -7 "-----------
why cant we just take x+4=3 => x= -1, and hence x-4=-5????
why are we taking |x+4| = 3??
root qs- 700 level, weird solution by mgmat!
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First of all, the problem is based on a principle which roughly put is:vkb16 wrote:If sqrt{(x+4)^2} = 3, which of the following could be
why cant we just take x+4=3 => x= -1, and hence x-4=-5????
why are we taking |x+4| = 3??
sqrt(x^2) = |x|.
Therefore, MGMT soln does this. If u know this, the prblm becomes easy.
This problem does not look like a 700 level problem.
The problem is pretty straight forward and involves 2 steps.
IMO, this is a 600 level Q.