Question

Evaluate 11X99 using suitable identity.(mention the identity)

Answer 1

Step-by-step explanation:

(110*99)

(100+10) * (100-1)

• Identity = x2 + (a+b)x +ab

(100)2 + (10+1)*100+1*10

10000 + 1100+10

11110

Answer 2

Answer:

11X99

(10+1) (10+89)

Here using 4th identity...

(x+a) (x+b) =x square+x(a+b) +ab

x=10, a=1, b=89

(10+1) (10+89) =10square+10(1+89) +1x89

=100+10(90) +89

=100+900+89

=1089.....