Triangular loop problem

This is a question I got wrong on a test and would like to see if I can get someone to show me how to do it properly. Snapped a pic . See below please. Thanks.

Attached Images
File Type: jpg 1397061439183.jpg (36.0 KB)
File Type: jpg 1397061473682.jpg (51.6 KB)

Leave a Reply

Name *
Email *