Question

Find the product :
(90+5)(90+12) if, x=90, a=5, b=12 and use identity (x+a)(x+b)=x^2+x(a+b)+ab

Answer 1

(90+5)(90+12)
=90^2+90(5+12)+5×12
=8100+90(17)+60
=8100+1530+60
=9690