Answer: See explanation
Explanation:
From the question, we are informed that the average weight of an American Quarter Horse at birth is 85 pounds and that they grow to a maximum weight of 1300 pounds.
The inequality to calculate the amount of pounds that an American Quarter Horse may gain from birth to adulthood will be the difference between it's maximum weight and weight at birth. This will be:
= 1300 - 85.
= 1215 pounds