Confsued on quant comparision q


here greg straight away chose the quantity A as ‘a’ and subtracted a from both sides leading to quantity A = 0 and a in quantity B getting cancelled out but I dont understand how he can simply eliminate the term

Dont we need to perform BODMAS here and calculate quantity B? so shouldnt we approach the terms to be divided first and then multiply and so on…

he took out what was common in both the expression and then subtracted it from both sides!