Answer
distance from point $C$ to point $A$ is $c=8.6mi$
Work Step by Step
The given points form a right triangle, so the dimension we are looking for is the hypotenuse of the triangle. We use the Pythagorean Theorem, where the side lengths are:
$a=7 mi$
$b=5mi$
Thus, we have:
$c^2=a^2+b^2$
$c = \sqrt {(7mi)^{2} + (5mi)^{2}}=8.6~mi$
