Question

The length of the base of a square pyramid is 15 inches. The slant height is 10 inches. What is the surface area of the pyramid?

Answer 1

@eliassaab

Answer 2

there is a direct formula, can you use it or you need to derive the formula ?

Answer 3

\(\large S A = a^2+2a \sqrt {\dfrac{a^2}{4}+h^2}\)

Answer 4

where a = base length = 15
h = height

Answer 5

oh, since slant height is directly given,
we can directly take
\(\Large SL = \sqrt {\dfrac{a^2}{4}+h^2}=10 \)
and your formula simplifies to
\(\Large SA =a^2+2a\times SL\)
a = 15, SL = 10
plug in! :)