Let a=b. Then a² =ab. a² + a² = a² + ab. 2a² = a² + ab. 2a² - 2ab = a² + ab - 2ab. 2a² - 2ab = a² - ab. This can be written as 2( a² - ab ) = 1( a² - ab ). Cancelling ( a² - ab ) from both side gives you 2=1. you comment which slide is wrong and why. Best answer will get a prize of 4 follow if not already, a shoutout, and a project that i will think of later
