Final answer:
The Giants have gained 5 yards in total.
Step-by-step explanation:
To represent how many yards the Giants have gained or lost, we need to add up the yards gained and subtract the yards lost. The Giants lost 5 yards three times, so the total yards lost would be 5 yards x 3 = -15 yards. They also gained 20 yards. To find the total yards gained, we add the positive number of yards gained to the negative number of yards lost: 20 yards + (-15) yards = 5 yards.
Therefore, the Giants have gained 5 yards in total.