Question

Using identify (x+a)(x+b)=x+(a+b)x+ab find the value of the following

46×48

Answer 1

46*48
=(40+6)(40+8)
Therefore x=40
a=6
b=8
Therefore using the formula
=x+(a+b)x+ab
=40+(6+8)40+6*8
=40+14*40+48
=40+56+48
=88+56
=144