Question

Find area of a trapezium whose parallel side are 60cm and 77cm non-parallel side are 25cm and 26cm

Answer 1

ABCD is a trapezium

ABDE is a parallelogram

BCE is a triangle

in triangle BCE

semiperimeter = (a+b+c )/2

= {25+26+(77-60)}/2

= (51+17)/2

=68/2

=34

area= $\\\sqrt{s(s-a)(s-b)(s-c)} \\= \sqrt{34(34-25)(34-26)(34-17)} \\= \sqrt{34(9)(8)(17)}\\= 17*3*4\\=204$

therfore here

1/2bh= 204

bh = 408

17h=408

h = 408/17

h = 24 cm

so now

area of parallelogram

= bh

= 60 * 24

= 1440 cm^2

therfroe

area of trapezium

= area of parallelogram + area of triangle

= 1440 + 204

= 1644 cm^2