Answer:
√29
Explanation:
(5, 10) and (10, 12) are separated horizontally by (10 - 5), or 5. This is the length of the horizontal leg of a triangle.
They are separated vertically by (12 - 10), or 2. This is the vertical leg length.
The distance (not difference) between the two points is then
(distance) = √( 5^2 + 2^2 ), or √(25 + 4), or √29