Detailed Example
Source: rootmath at YouTube: https://www.youtube.com/watch?v=1TK69SVQNPk
Source: rootmath at YouTube: https://www.youtube.com/watch?v=Ul1VcgpU1Fw
Source: Phil Clark at YouTube: https://www.youtube.com/watch?v=sOd09PbvZRk
Source: Khan Academy at YouTube: https://www.youtube.com/watch?v=MC0tq6fNRwU
Source: Mario's Math Tutoring at YouTube: https://www.youtube.com/watch?v=UvTYc5Wqu8w