Question

ABCD is a trapezoidal ground AD = 9m , BD = 41m, CD = 15m and angle a = 90 degrees.Find the area and perimeter of the ground.
*Whoever will give the answer first, I will mark his/her brainliest*​

Answer 1

Step-by-step explanation:

Let ABCD be a quadrilateral, then

AB=9m,BC=40m,CD=28m,DA=15m & ∠ABC=90

∘

ar□ABCD=ar△ABC+ar△ACD

In △ABC, using Pythagoras theorem,

AC

2

=AB

2

+BC

2

⇒AC=

9

2

+40

2

=

1681

=41m

ar△ABC=

2

1

×AB×BC=

2

1

×9×40=180m

2

ar△ACD=

s(s−a)(s−b)(s−c)

,S=

2

a+b+c

=

2

15+28+41

=42m

=

42(42−15)(42−28)(42−41)

=

42×27×14×1

=126m

2

∴ar□ABCD=180+126=306m

2