Answer:
Choice C is correct answer.
Step-by-step explanation:
We have to find the surface area of of regular pyramid.
From given diagram , we observe that
Base = 9 units height = 7 units
The formula for total surface area of pyramid is
T.S.A = L.S.A + B
Total surface area of regular pyramid is sum of Lateral surface area and area of base.
L.S.A = 1/2pl where p is perimeter and l is height.
B = s² is area of base where s is base.
Hence, T.S.A = 1/2pl+ s²
Firstly, we have to find the perimeter.
p = 4s
p = 4(9) = 36 units
T.S.A = 1/2(36)(7)+(9)²
T.S.A = (18)(7) + 81
T.S.A = 126+81
T.S.A = 207 units.
Hence, the surface area of regular pyramid of 207 units.
