Question

The figure below shows a parallelogram PQRS.


The flowchart shown below shows the sequence of steps to prove the theorem, Opposite angles of a parallelogram are equal.



Which option best represents x and y? (5 points)


x = angle 1 is equal to angle 6 and y =corresponding angles

x = angle 5 is equal to angle 3 and y = interior opposite angles

x = angle 5 is equal to angle 6 and y = supplementary angles

x = angle 4 is equal to angle 3 and y = alternate interior angles

Answer 1

oohh i didnt know it was that kind, sorry i cant help you there

Answer 2

ok

Answer 3

@LynFran

Answer 4

i think D

Answer 5

Why tho?

Answer 6

because if u look at the top ..angle 1=angle2
so angle 3 must = angle 4

Answer 7

http://www.mathopenref.com/parallelogramangles.html

Answer 8

look how the angles are = in the link provided

Answer 9

o ok. and can I ask you another question?

Answer 10

sure

Answer 11

Look at the quadrilateral shown below.



Elba writes the following proof for the theorem, If the diagonals of a quadrilateral bisect each other, the quadrilateral is a parallelogram.

Elba's proof

1. For triangles AOB and COD, angle 1 is equal to angle 2 as they are vertical angles.
2. AO = OC and BO = OD because it is given that diagonals bisect each other.
3. Therefore, the triangles AOB and COD are congruent by SAS postulate.
4. Similarly, triangles AOD and COB are congruent.
5. By CPCTC, angle ABD is equal to angle CDB and angle ADB is equal to angle CBD.
6. As the corresponding angles are congruent, the opposite sides of quadrilateral ABCD are parallel.
7. Therefore, ABCD is a parallelogram.

Which is the first incorrect statement in Elba's proof? (5 points)


Statement 6


Statement 4


Statement 3


Statement 5

Answer 12

k

Answer 13

statement 3 and 4 correct

Answer 14

So it is either 6 or 5 that is not correct?

Answer 15

yes thats what im trying to figure out which 1 of the 2 is incorrect i cant remember the CPCTC principle..

Answer 16

https://www.google.com/search?q=cptc+principle&oq=cptc+principle&aqs=chrome..69i57.6013j0j1&sourceid=chrome&es_sm=93&ie=UTF-8#q=cpctc+geometry

Answer 17

I think it is 6.

Answer 18

it is 6.
thank you for your help

Answer 19

ok

Answer 20

welcome