Answer:
-5
Step-by-step explanation:
You can work backwards with this problem if that helps you.
so, what times 3 = -15
-5 times 3 = -15 so that would be the answer
Remark
The number of faces reaching out in the 3rd dimension of the pyramid = the number of edges on the base.
Givens
Number of edges (or sides on the base)= e
Number of faces = f
Formula
F = e + 1 Don't forget that the base is also a face.
