Question

A convex polyhedron has 30 edges and 8 fewer vertices than faces. How many faces does the polyhedron have?

Answer 1

20

.......

Explanation:

used desmos- formula was: x+(x-8)=32

Answer 2

formula for polyhedrons is V-E+F=2

F= faces = unknown F

V= vertices=F-8

E= edges=30

(F-8)-30+F=2

add the 2 F's and 30 & 8 so you get 2F-38=2

ince -38 doesn't have variable move it to other side by adding 38 to both sides

2F=38+2 which becomes 2F=40

now divide both sides by 2 to get F=20 so there are 20 faces