Surface Area of a Triangular Prism

The surface area of a triangular prism is the entire space occupied by its outermost layers (or faces). It is expressed in square units such as m², cm², mm², and in².

Formulas

Like all 3-dimensional shapes, 2 types of surface areas can be calculated for a triangular prism.

Lateral Surface Area

The lateral surface area (LSA) of a triangular prism is only the sum of the areas of all its faces except the bases. The formula to calculate the total and lateral surface area of a triangular prism is given below:

Let us solve an example to understand the concept better.

Find the lateral surface area of a triangular prism given in the figure.

Solution:

As we know,
Lateral Surface Area (LSA) = (s₁ + s₂ + s₃) × l, here s₁ = 4 in, s₂ = 6 in,  s₃ = 8 in, l = 9.6 in
= 18 × 9.6
= 172.8 in²

Total Surface Area

The total surface area (TSA) of a triangular prism is the sum of the lateral surface area and twice the base area. The formula to calculate the TSA of a triangular prism is given below:

Find the total surface area of a triangular prism given in the figure.

Solution:

As we know,
Total Surface Area (TSA) = (b × h) + (s₁ + s₂ + s₃) × l, here, s₁ = 5 cm, s₂ = b = 6 cm, s₃ = 7 cm, h = 4.9 cm, l = 12 cm.
∴TSA = (6 × 4.9) + (5 + 6 + 7) × 12
 = 245.4 cm²

• More Resources:
  • Volume of a Prism
  • Surface Area of a Prism
  • Right Prism
  • Oblique Prism
  • Rectangular Prism
  • Volume of a Rectangular Prism
  • Surface Area of a Rectangular Prism
  • Triangular Prism
  • Volume of a Triangular Prism
  • Surface Area of a Triangular Prism
  • Hexagonal Prism
  • Volume of a Hexagonal Prism
  • Surface Area of a Hexagonal Prism
  • Pentagonal Prism
  • Volume of a Pentagonal Prism
  • Surface Area of a Pentagonal Prism
  • Trapezoidal Prism
  • Volume of a Trapezoidal Prism
  • Surface Area of a Trapezoidal Prism
  • Square Prism
  • Volume of a Square Prism
  • Surface Area of a Square Prism
  • Octagonal Prism
  • Heptagonal Prism
  • Decagonal Prism