Free help with homework

Why join Brainly?

  • ask questions about your assignment
  • get answers with explanations
  • find similar questions


Let ABCD a  ||gm
: opposite sides eaqual AB=CD and AD=BC
AC=BD |given
AB=BA |common
Therfore triangle ACB is Congurrent to triangle BDA
<ACB = < BAD (1) | by cpct
Again AD || BC
AD || BC and transversal AB intersects thm
<BAD + <ABC =180 (2)| SUm of consecutive interrior angleson the same side of the transversal is 180 degree

FROM (1) and (2)
<BAD=<ABC=90 degree
therfore <A= 90 degree and <b =90 degree
Similarly we can prove <c=90 degree and <D=90 degree

Therfore ABCD is A triangle

NOTE: < is used for ANGLE and ||gm for parallelogram and || for parallel


0 0 0
dude...u r supposed to write ABCD is a rectangle...not a triangle
sorry by mistake'
i gota type alot fo this :P  ;)
chill...just told coz that guy might get confused
Let the parallelogram be ABCD and AC and BD are its diagonals
AD=BC(opp. sides of a parallelogram are equal)
∴By SSS congruence rule 
ΔADC is congruent to ΔBCD
by cpct
Since in a parallelogram adjacent angles are supplementary
and since ∠ADC=∠BCD
since in a parallelogram adjacent angles are 90°, the parallelogram is a rectangle.
Hence Proved
0 0 0
The Brain
  • The Brain
  • Helper
Not sure about the answer?
Learn more with Brainly!
Having trouble with your homework?
Get free help!
  • 80% of questions are answered in under 10 minutes
  • Answers come with explanations, so that you can learn
  • Answer quality is ensured by our experts