Answer:
Tanya read 5 nonfiction books and 7 fiction books.
Explanation:
Given that:
Number of books read by Tanya = 12
Points for nonfiction book = 3.5
Points for fiction book = 1.5
Total credit points received = 28
Let,
x be the number of nonfiction book read
y be the number fiction books read
According to given statement;
x+y=12 Eqn 1
3.5x+1.5y=28 Eqn 2
Multiplying Eqn 1 by 1.5
1.5(x+y=12)
1.5x+1.5y=18 Eqn 3
Subtracting Eqn 3 from Eqn 2
(3.5x+1.5y)-(1.5x+1.5y)=28-18
3.5x+1.5y-1.5x-1.5y=10
2x=10
Dividing both sides by 2
Putting x=5 in Eqn 1
5+y=12
y=12-5
y=7
Hence,
Tanya read 5 nonfiction books and 7 fiction books.