https://schools.aglasem.com/2281
https://www.careerlauncher.com/cbse-ncert/class-8/Math/CBSE-ExponentsandPowers-NCERTSolutions.html
refer the above links for the explantion
this is a video lecture link please watch it for the chapter
https://www.youtube.com/watch?v=3RLlAfYBFjE