Answer:
Step-by-step explanation:
You can use Heron's formula for this question.
Heron's Formula: Area of Triangle = root s(s-a)(s-b)(s-c)
Where s = perimeter/2 and a, b, and c are the side lengths.
So solving...
s = perimeter/2
= (9yd + 3yd + 8yd)/2
= 20yd/2
= 10yd
A = root 10yd(10yd-9yd)(10yd-3yd)(10yd-8yd)
= root 10yd(1yd)(7yd)(2yd)
= root 140yd
= 2 root 35