Each side edge of the pyramid is 13 cm. The base of the pyramid is a right-angled triangle
Each side edge of the pyramid is 13 cm. The base of the pyramid is a right-angled triangle with legs 6 cm and 8 cm. Find the surface area of the pyramid.
Let us determine the length of the hypotenuse AB of the base of the pyramid.
AB ^ 2 = BC ^ 2 + AC ^ 2 = 64 + 36 = 100.
AB = 10 cm.
Determine the area of the base of the pyramid.
Sbn = АС * ВС / 2 = 6 * 8/2 = 24 cm2.
The areas of the side faces are determined by Heron’s theorem.
Let’s define the perimeters of the side faces.
Dist = 13 + 13 + 6 = 32 cm, then p (asd) = 32/2 = 16 cm.
Then Sacd = √16 * 3 * 3 * 10 = √1440 = 12 * √10 cm2.
Rvsd = 13 + 13 + 8 = 34 cm, then p (asd) = 34/2 = 17 cm.
Then Svsd = √17 * 4 * 4 * 9 = √2448 = 12 * √17 cm2.
Ravd = 13 + 13 + 10 = 36 cm, then p (asd) = 36/2 = 18 cm.
Then Savd = √18 * 5 * 5 * 8 = √3600 = 60 cm2.
Spov = Smax + Sasd + Svsd + Savd = 24 + 12 * √10 + 12 * √17 + 60 = 12 * (7 + √10 + √17) cm2.
Answer: The surface area is 12 * (7 + √10 + √17) cm2.