Question

I need answer for this 3 sums

Answer 1

1problem
given thatabcd ia paralellogram
in triangle afd and triangle bec
af=be(opp sides of a rectangle
ad=bc(opp sides of papallelogram)
df=ce(ab=dc=de+ec
           ab=ef=de+df)
afdcongruent to bec(sss congruence)
  


2
abcd is a rhombus
let acand bd meet at o
oab=ocd
ab=cd
oba=odc
aod congruent to cod
ao=oc(cpct)
aod congruent to cod
similarly we can prove
aodcongruent to cod
from 123 we have
 diognals of rhombus divide in to 4 congruent triangles
 



3
in quadrilateral abcd a+B+C+D=360
1|2c+d+=180-1\2(a+b)
1|2c+1|2d+cod=180
1|2c+1|2d=180-cod
1|2(c+d)=180-cod
from1 2
180-cod=180-1|2(a+b)cod=1|2(a+b)