......................12....................
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*...........................7...............*
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*.............*..............................*
*.............*..............................*
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a............-3.............................b
Referring to the diagram, what is the value of a - b?
a. -12 b. -4 c. 4 d. 12
if you have enough time, may i ask for you the formula?
thanks a lot!!! ^^
another things, i wanna ask how to post photo in yahoo question.
thanks for your help!