Hi,
I think to meet the condition, x must be positive, but why 2) meet the condition?? the answer is B but could not figure out,..
test 19 #20
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sqrt [ (x-3)^2 ] will yield a positive answer. Now, depending on thedunkin77 wrote:Hi,
I think to meet the condition, x must be positive, but why 2) meet the condition?? the answer is B but could not figure out,..
sign of x, it will be either x-3 or 3-x.
1 - insufficient. x can be > 3 or < 3. So, we don't know if it will be
equal to 3-x
2 - sufficient. -x|x| will be positive when x is negative. Since x is
negative, the final answer will be 3-x and hence sufficient.