Answer:surface area = 2x^2 + 18x - 34
Explanation:
The formula for determining the surface area of a rectangular prism is expressed as
Surface area = 2lh + 2wh + 2wl
Where
l represents the length of the rectangular prism.
h represents the height of the rectangular prism.
w represents the width of the rectangular prism
From the information given,
l = x+3
h = 5
w = x - 4
Surface area = 2 × 5 × (x+3) + 2 × (x - 4) × 5 + 2 × (x - 4) × (x + 3)
= 2(5x + 15) + 10(x - 4) + 2[x^2 + 3x - 4x - 12]
= 10x + 30 + 10x - 40 + 2x^2 - 2x - 24
= 2x^2 + 18x - 34