Answer:
15 miles
Explanation:
It is given that,
Shane could drive due north to get to his parents' house or he could drive due east to get to his grandparents' house.
It is 8 miles from Shane's house to his parents' house and a straight-line distance of 17 miles from his parents' house to his grandparents' house.
It can be calculated by considering a right angled triangle. Using pythagoras theorem, we can find the distance between Shane from his grandparents' house. Let it is d.

Hence, Shane is 15 miles from his grandparents' house.