Answer:
144 cm ²
Explanation:
The surface area of a right triangular prism is made up of 2 congruent triangles (these are called the "bases") and 3 rectangles.
Surface area of a right triangular prism formula
Surface area = (S₁ + S₂ + S₃)L + bh
where:
- S₁, S₂ and S₃ are the side lengths of the triangle
- L is the length of the prism
- b is the length of the base of the triangle
- h is the height of the triangle
⇒ Surface area = (3 + 4 + 5)11 + 4 × 3
= (12)11 + 12
= 132 + 12
= 144 cm²