Let's plug the coordinate point values into the equation: [tex] \sqrt{(3-1)^{2} +(1-3)^{2} } [/tex] (1,3) is x₁ and (3,1) is x₂ Begin to simplify within the parenthesis: [tex] \sqrt{2^{2}+(-2)^{2} } [/tex] Square the two numbers: [tex] \sqrt{4 + 4} [/tex] Add the two to get: [tex] \sqrt{8} [/tex] Since 8 is not a square number, this is as far as we can simplify this. Hope this helps!