Question

A right square pyramid has a surface area of 75.5m^2 and a base length of 3.5m. What is the slant height of this right pyramid?

Answer 1

Clearly the surface area would consist only of the 4 triangles.
area of one of them = 75.5/4 or 18.875 m^2

area = (1/2)base x height
18.875 = (1/2)(3.5)h
h = 2(18.875)/3.5 = appr 10.7857

clean up to whatever accuracy is expected
I would say 10.8 , since the original data had one decimal

Answer 2

but the answer is 9.0 and 10.8 won't work for the other questions :(

Answer 3

define what you mean by slant height.

Answer 4

the height that's not at the center but on the side?

Answer 5

then I am right

check:

area of one triangle = (1/2)(3.5)(10.7857
= 18.875

4 such triangle = 4(18.875) = 75.5