The answers is A= C/-13
C= 13A
-9/2 = -1/4(-2)+ b
-9/2 = 1/2 + b
Minus 1/2 over
B= -5
Hope this helps!
In order to find out the answer , you just need to count :
Let's say that mary's collection is symbolized by x
2/3 x = 4h
x = 3/2 . 4h
x = 6h
The storybooks they have in total would be : 6h + 4h = 10 h
hope this helps