Answer:
$4.72
Step-by-step explanation:
16.79+28.49=45.28
50-45.28=4.72
12/3 is rational
DescriptionIn mathematics, a rational number is a number that can be expressed as the quotient or fraction
Step-by-step explanation:

• y2 → -1
• y1 → 5
• x1 → 4
• x2 → -3

1 pound = 16 oz
Her books weigh 9 pounds or (9)(16)= 144 oz
Math Textbook= 40 oz
Biology textbook= 3 pounds or (3)(16)= 48 oz
Total weight of books - math textbook - biology textbook = science textbook
144-40-48 = 56oz
science textbook = 56oz