Question

please help.me solve this one​

Answer 1

Answer:

ar(∆ABD)=75 cm^2

75=1/2*b*h

75=1/2*10*h

75=5h

h=15

height of triangle ACD =height of trapezium

ar(ABCD)=1/2*(sum of parallel sides)*height

ar(ABCD)=1/2*(10+18)*15

ar(ABCD=1/2*28*15

ar(ABCD)=14*15

ar(ABCD)=210cm square