If there are 12 books in the rack, a person has to choose 5
out of them. In how many ways
can he choose s books
book is
never selected,
how many ways
If one book is never selected​?

462 ways

Step-by-step explanation:

One book never selected means 12 - 1 = 11.

So to find the number of ways, 11C5 which equals to: 11!/(5!(11-5)!) = 462

the answers are in the images, i received 100% on this assignment. hope this !

first, you divide the triangle in two, tô form a retangle triangle. after, using pythagoream theorem:

18^2 = 14^2 + (x/2)^2

(x^2/4) + 196 = 324

x^2/4 = 324 - 196

x^2/4 = 128

x^2 = 512

x = √512

x = √2^9

x = 16√2 cm

i hope i you.