Carla made a border for her garden using parallelogram shaped tiles. each piece had a base of 4 inches and a height of 2.5 inches. she used 85 tiles. what was the total area of the border

For each piece we have that the area is:
 A = (b) * (h)
 Where,
 b: base of the parallelogram
 h: height of the parallelogram
 Substituting values:
 A = (4) * (2.5)
 A = 10 in ^ 2
 Then, for 85 pieces we have:
 (85) * (10) = 850 in ^ 2
 
 the total area of the border was:
 850 in ^ 2

It’s going to be d. 4x^2-4x-19’