Respuesta :
Let
x-------> the number of fiction books
y-------> the number of nonfiction books.
we know that
[tex] x+y=26 [/tex] -----> equation [tex] 1 [/tex]
[tex] x=y+12 [/tex]
[tex] x-y=12 [/tex] -----> equation [tex] 2 [/tex]
Add equation [tex] 1 [/tex] and equation [tex] 2 [/tex]
[tex] x+y=26\\x-y=12\\ ------\\ 2x=38\\ x=38/2\\x=19\ fiction\ books[/tex]
find the value of y
[tex] x+y=26 [/tex]
[tex] 19+y=26 [/tex]
[tex] y=26-19=7\ nonfiction\ books [/tex]
therefore
the answer is
Part a) the number of fiction books is [tex] 19\ fiction\ books [/tex]
Part b) the number of nonfiction books is [tex] 7\ nonfiction\ books [/tex]