Answer:
21yd^2
Explanation:
join the centre to all the vertex,
since this figure is of regular pentagon, it's will form 5 equal triangle of equal area!
now area of one such triangle is
1/2 ×base ×height
=1/2 ×3.5x2.4 (yd^2)
=4.2 yd^2
now the pentagon is sum of 5 such equal triangle,so it's are will be
5×4.2 (yd^2)
=21 yd^2
✌️:)