Question

solve 71 square - 69 square (formula based sum )​

Answer 1

Answer:

71² - 69²

= a² - b² = (a+b)(a-b)

= (71 + 69)(71 - 69)

= 140*2

= 280

Answer 2

Answer:

${71}^{2} - {69}^{2}$

${(70 + 1)}^{2} - {(70 - 1)}^{2}$

we know that,

${(x + y)}^{2} - {(x - y)}^{2} = 4xy$

=} coming to question , by using above formula it's,

$4 \times 70 \times 1 = 280$

therefore the answer is 280

$\infty ammu4763$