Answer:
$6/ book
Step-by-step explanation:
Unit price = Total cost/ total number of items
= 90/15
=$6 per book
The slope should be 3/2, since you rise 3 and go over 2
2/21 * 7/8
14/168
divide top and bottom by 14
1/12
-7(2)+y=60
-14+y=60
y=60+14
Y=74