Question

how to solve 30.8×29.2 using identities​

Answer 1

Step-by-step explanation:

We know, 8.3×7.7=(8+0.3)(8−0.3),

where a=8 and b=0.3.

Now, solve as shown below:

8.3×7.7

=(8+0.3)(8−0.3)=8

2

−(0.3)

2

⇒8.3×7.7=64−0.09

⇒8.3×7.7=63.91.

Hence, 8.3×7.7=63.91

Answer 2

Answer:

Step-by-step explanation:

30.8 × 29.2

= ( 30 + 0.8 ) × ( 30 - 0.8 )

= ( 30 )² - ( 0.8 )²

= 900 - 0.64

= 899.36 is the answer.