Answer:
If the shape of end face has n sides
Then, in total, there are n+2 faces
Using that formula
Faces in 20-sided polygon = n+2 = 20+2 = 22
Step-by-step explanation:
Pls vote as brainliest
First, recall that

So if
, then
.
Second,

We know that
and
, which means we should also have
.
Third,

but as we've already shown, we need to have
, so we pick the negative root.
Finally,

Unfortunately, none of the given answers match, so perhaps I've misunderstood one of the given conditions... In any case, this answer should tell you everything you need to know to find the right solution from the given options.
Process:
2/3x -7 = 17
17 + 7 = 24
2/3x = 24
2/3 = 24/x
24 ÷ 2 = 12
12 x 3 = 36
x = 36
Answer: X = 36
Volume = 1/3*a^2*h
So, V = (36*7)/3
= 84