Question

What is the distance between (1,-10) and (2,7)?

Answer 1

We can use the Pythagorean Theorem for this. Draw a right triangle whose shorter sides are along the lines of the grid so that the horizontal side has a length of 1 and the vertical side has a length of 17. The hypotenuse would be \[\sqrt{1^2+17^2}\] equal to \[\sqrt{290}\]

Answer 2

as a generalisation of what @HarryPotter5777 said.
We derived the distance formula bet two points (x1, y1) and (x2,y2)
D = xqrt[(x2-x1)^2+(y2-y1)^2]