Answer:
1.8 miles
Explanation:
Let's figure out the total distance he has actually ridden: 3 + 3 = 6 miles.
Now, let's draw this out (see attachment). Notice that if Keith rode his bike directly to the pool, we'd have a right triangle with legs 3 and 3 and with the hypotenuse as the direct path.
Use the Pythagorean Theorem to figure out the hypotenuse length:
c = √(3² + 3²) = √(9 + 9) = √18 = 3√2 ≈ 4.2 miles
Subtract this from 6:
6 - 4.2 = 1.8
The answer is 1.8 miles.