## ze4life 2 years ago State the principal definition or theorem that enables you to deduce or prove, from the information given,that quadrilateral PQRS is a parrallelogram. PQ=SR;PQ||SR PQ||SR;PS||QR <PSR=RQP;<SRQ=QPS PQ=SR;PS=QR PA=1/2 PR;SA=1/2 SQ

1. Directrix

@ze4life Please provide the diagram and instructions. This looks as if it might be a question about various quadrilaterals.

2. exitfreshly

What exactly is the end result you are trying to deduce or prov, of the statements given?

3. ze4life

|dw:1359763252515:dw|

4. Directrix

The attached chart displays the theorems used to prove that a quadrilateral is a parallelogram. Please review them.

5. Directrix

@ze4life I'll help you get started by working the first two problems. ------------ 7) If one pair of opposite sides of a quadrilateral are both congruent and parallel, the quadrilateral is a parallelogram. |dw:1359783930539:dw|

6. Directrix

8) A quadrilateral with both pairs of opposite sides parallel is a parallelogram. You can just answer "Definition of parallelogram." |dw:1359784112088:dw| @ze4life If you post what you think are the reasons for problems 9 -11, I will check them for you.

7. ze4life

i cant understand

8. AnElephant

all of these are requirements for a parallelogram based on the definition of a parallelogram, in other words, it is defined to be the shape where all of these things hold true

9. Directrix

@ze4life Learn the Geometry theorems and you will be able to understand how to do the problems.