Question

find the product of given numbers using appropriate identitie
a. 125x75
b. 101x99 ​

Answer 1

Answer:

a. 9375

b. 9999

Step-by-step explanation:

a.

ATQ,

$125 \times 75$

We can also write this as

$(100 + 25) \times (100 - 25)$

We use the following identity

$(x + y)(x - y) = {x}^{2} - {y}^{2}$

Where,

x = 100

y = 25

So, we get

${100}^{2} - {25}^{2}$

$10000 - 625$

$9375$

b.

ATQ,

$101 \times 99$

We can also write it as

$(100 + 1) \times (100 - 1)$

We use the similar identity as the above question

$(x + y)(x - y) = {x }^{2} - {y}^{2}$

Where,

x = 100

y = 1

So, we get

${100}^{2} - {1}^{2}$

$10000 - 1$

$9999$