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by nickhar130 » Fri Nov 05, 2010 10:55 am
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In the quadrilateral CDEF, CD//EF and DE//CF. Do all sides CDEF have the same length?

1) CE = DF

2) All angles of triangle CDF are the same.
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by Night reader » Fri Nov 05, 2010 5:13 pm
nickhar130 wrote:Image


In the quadrilateral CDEF, CD//EF and DE//CF. Do all sides CDEF have the same length?

1) CE = DF

2) All angles of triangle CDF are the same.
Statement (1) is not sufficient as CE=DF is a general condition for all quadrilaterals;
Statement (2) assumes all angles in triangle CDF are equal; all sides must be equal then. The opposite angles are equal in quadrilateral. We have got all sides being equal in this case.

Pick (B), statement (2)
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by nickhar130 » Sat Nov 06, 2010 10:36 am
I'm understanding condition 1, but for condition 2 if angle CDF are the same, then the opposite angle perhaps angle CFE are same and therefore we assume all sides are same? Can you please elaborate more on this because I lack the knowledge of what is given and which opposite angles are assumed to be the same.
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