Question

Using euler formula find unknown in table

Answer 1

Answer:

the answers are as follows:-

a) 6

b) 9

c) 20

Answer 2

Answer:

$\large{\red{\underline{Euler's\;Formula}}}$

Faces+vertices=Edges+2

By putting the above formula in our questions ,we get :

In first case :

$8 + x1 = 12 + 2 \\ \implies \: 8 + x1 = 14 \\ \implies x1 = 14 - 8 \\ \implies \: x1= 6$

Second case :

$5 + 6 = x2 + 2 \\ \implies \: 11 = x2 + 2 \\ \implies \: x2 = 11 - 2 \\ \implies \: x2 = 9$

Third case :

$x3 + 12 = 30 + 2 \\ \implies \: x3+ 12 = 32 \\ \implies \: x3 = 32 - 12 \\ \implies \: x 3 \: = 20$