Question

USING
(x + a)(x + b) = {x}^{2} + (a + b)x +ab(x+a)(x+b)=x
2
+(a+b)x+ab
FIND​​

Answer 1

(i)

103 * 104

=> (100 + 3) * (100 + 4)

=> (100)² + (3 + 4) * 100 + (3)(4)

=> 10000 + 700 + 12

=> 10712

(ii)

5.1 * 5.2

=> (5 + 0.1)(5 + 0.2)

=> (5.1)² + (0.1 + 0.2) * 5 +  (0.1)(0.2)

=> 25 + 1.5 + 0.02

=> 26.52

(iii)

103 * 98

=> (100 + 3)(100 - 2)

=> (100)² + (3 - 2) * 100 + (3)(-2)

=> 10000 + 100 - 6

=> 10094

(iv)

9.7 * 9.8

=> (9 + 0.7)(9 + 0.8)

=> (9)² + (0.7 + 0.8) * (9) + (0.7)(0.8)

=> 81 + 13.5 + 0.56

=> 95.06

#Mark As Brainliest

Answer 2

HERE IS YOUR ANSWER

1. 103+104

=(100+3)(100+4)

=100^2 + (3+4)100 + (3×4)

= 1000+700+12

= 10712

2. 5.1×5.2

=(5+0.1)(5+0.2)

=5^2 + (0.1+0.2)5 + (0.1×0.2)

= 25+1.5+0.02

= 26.52

3. 103×98

=(100+3)(100-2)

= 100^2 + (3-2)100 + (3×-2)

= 1000+100-6

= 10094

4. 9.7×9.8

=(9+0.7)(9+0.8)

= 9^2 + (0.7+0.8)9 + (0.7×0.8)

= 81+13.5+0.56

= 95.06