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It is difficult to give a proof without diagrams, but here goes:
Suppose you have the parallelogram with ABDC and ADBC
Then angle ABC = angle CDA.
Now draw the diagonal AC.
Then angle ACB = angle CAD (alternate angles).
So, in triangles ABC and ACD,
two pairs of angles are equal so that all three pairs are equal (in each triangle the three add to 180 deg).
and AC is a common side.
So the two triangles are congruent and so AB = DC and AD = BC
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∙ 14y ago
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Are parallelogram has opposite sides?
A parallelogram has opposite equal parallel sides
What is the 3 properties of special parallelogram?
Opposite sides are parallel; opposite sides are equal; opposite angles are equal.
Four sides opposite sides equal no sides perpendicular?
Parallelogram.
A plain figure with opposite sides are equal?
it may be a parallelogram or a kite both have opposite sides equal
What is a parallelogram with 4 equal sides and 4 opposite sides?
A rhombus.
Are parallelogram has opposite sides?
A parallelogram has opposite equal parallel sides
The opposite sides of a parallelogram are?
The opposite sides of a parallelogram are both parallel and equal.
Does a parallelogram have two pairs of equal sides?
opposite sides of a parallelogram are equal.
Is a trapiozd a parallelogram?
No. A parallelogram has opposite sides equal
What does parallelogram?
it has all equal sides That's a special case of a parallelogram called a rhombus. A parallelogram has opposite sides equal and parallel.
What is the 3 properties of special parallelogram?
Opposite sides are parallel; opposite sides are equal; opposite angles are equal.
Is a rhombus a parrallelogram why or why not?
Both pairs of opposite sides of a parallelogram must be equal. Since both pairs of opposite sides of a rhombus are equal, it is a parallelogram.
Four sides opposite sides equal no sides perpendicular?
Parallelogram.
A plain figure with opposite sides are equal?
it may be a parallelogram or a kite both have opposite sides equal
A rhombus is a parallelogram?
Yes. A parallelogram has two pairs of opposite sides parallel (and each pair of equal length). A rhombus has two pairs of opposite sides parallel (and each of those pairs of opposite sides are of equal length), thus it is a parallelogram. It is a special case of parallelogram where all four sides are equal in length, not just the opposite pairs.
Does a parallelogram have equal sides?
A rhombus is a parallelogram with 4 equal sides. Many parallelograms do not have 4 equal sides. All parallelograms have 2 pairs of equal opposite sides.
How many point does a parallelogram have?
A parallelogram. Opposite sides are parallel and congruent.parallelogram is a quadrilateral with two sets of parallel sides. The opposite sides of a parallelogram are of equal length, and the opposite angles of a parallelogram are congruent. The three-dimensional counterpart of a parallelogram is a parallelepiped.Parallelogram - A quadrilateral whose opposite sides are parallel
