What is the length of LINE GH?
And please explain why thank you:

co-ordinates of point G are (1,2)
co-ordinates of point H are (3,-3)
so, by distance formula :
[tex] \sqrt{( {x1 - x1})^{2} + ( {y1 - y2})^{2} } \\ = \sqrt{( {1- 3})^{2} + ( {2 - ( - 3)})^{2} } \\ \sqrt{( { - 2})^{2} + ( {2 + 3})^{2} } \\ \sqrt{( { - 2})^{2} + ( {5})^{2} } \\ \sqrt{4 + 25} \\ \sqrt{29} [/tex]
so, it is root(29) or 5.38 units