Answer:
12-4√5
Step-by-step explanation:
(√10-√2)²
(√10-√2)(√10-√2)
Foil/distribute
10-√20-√20+2
12-2√20
12-2√4*√5
12-2*2√5
12-4√5
Radius is MN
Cord is TR
Hope this helps
Only two questions came up
The distance formula is:

We are given two points in the form (x,y), so plug in the values to the distance formula:

Next we can simplify. We know that 12-12 is 0, so we can drop it from the equation, as it will not affect our answer. Also, we know that -10-15 is -25:

The square and square root cancel each other out leaving us with 25.
The answer is 25.