Question

find the perimeter and area of a quafrilateral and in which ab= 17cm , ad=9cm ,CD =12cm, acb = 90 degree and a.c. = 15cm .

Answer 1

in triangle ACB,

by using pythagoras theorem

(ab)^2=(ac)^2+(bc)^2

(17)^2=(15)^2+(bc)^2

289-225=(bc)^2

(bc)^2=64

bc=8cm

perimeter=ab+bc+cd+ad

=17+8+12+9

=46cm

area(abcd)=area(adc)+area(acb)

area(adc)=1/2*dc*ad

=1/2*12*9

=54cm^2

area(acb)=1/2*ac*bc

=1/2*15*8

=60cm^2

area(abcd)=54+60=114cm^2