The surface area is equal to the sum of the areas of the triangles that form the red.
Area of a triangle:
[tex]A=\frac{1}{2}b\cdot h[/tex]
The b is the base or the lenght of the triangle
h is the height
As the 4 triangles have the same measures, the surface area of the pyramid is:
[tex]\begin{gathered} SA=4(\frac{1}{2}b\cdot h) \\ \\ SA=4(\frac{1}{2}(6in)(4in)) \\ \\ SA=4(12in^2) \\ \\ SA=48in^2 \end{gathered}[/tex]Then, the surface area is 48 square inches
