EXPLANATION
Let's see the facts:
The coordinates of the dinosaur bones are:
(x_1,y_1) = (300,100)
The coordinates of the whale bones are:
(x_2,y_2) = (300, -200)
Applying the distance equation will tell us how far apart are them:
![\text{distance = }\sqrt[]{(x_2-x_1)^2+(y_2-y_1)^2}](https://img.qammunity.org/2023/formulas/mathematics/college/kfmwke8t5a5bxiszg9fn6v4eip1962salc.png)
Substituting terms:
![\text{distance = }\sqrt[\square]{(300-300)^2+(-200-100)^2}](https://img.qammunity.org/2023/formulas/mathematics/college/zldy819c9a836nirqf587panyfyggamr5v.png)
Adding numbers:
![\text{distance = }\sqrt[]{(-300)^2}](https://img.qammunity.org/2023/formulas/mathematics/college/bfakyfu1zuyfvxibdmej0xzf4s0r7g7ikd.png)
Solving the power:
![\text{distance = }\sqrt[]{90,000}](https://img.qammunity.org/2023/formulas/mathematics/college/rt03sqowlapb7aiw6vom1h83h2hecambnw.png)
Solving the root:

The distance is 300 miles.