Answer:
SA = 225 cm²
Step-by-step explanation:
The given pyramid dimensions are;
The length of the rectangular base of the pyramid, l = 12 cm
The width of the base, w = 6 cm
The area of the rectangular base, Aₐ = 12 cm × 6 cm = 72 cm²
The height of one of the triangles forming the side of the pyramid, h₁ = 8 cm
The base length of the above triangle, b₁ = 12 cm
The area of the above triangle, A₁ = (1/2)×12 cm × 8 cm = 48 cm²
The height of the other of the triangles forming the other side of the pyramid, h₂ = 9.5 cm
The base length of the above triangle, b₂ = 6 cm
The area of the above triangle, A = (1/2) × 9.5 cm × 6 cm = 28.5 cm²
The surface area of the pyramid, SA = Aₐ + 2 × A₁ + 2 × A₂
Therefore;
SA = 72 cm² + 2 × 48 cm² + 2 × 28.5 cm² = 225 cm²
SA = 225 cm²