Question

Answer quick it's urgent

Expand : (5xy+7)(5xy-7)
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Answer 1

25x²y² - 49

Explanation:

We can do this by using the a+b formula:

(a+b)(a-b)= a² - b²

So,

(5xy+7)(5xy-7)

=(5xy)² - 7²

= 25x²y² - 49

Another way we can do this by expanding the algebraic expression:

(5xy+7)(5xy-7)

= 5xy(5xy-7) + 7(5xy-7)

= 25x²y² - 35xy + 35xy - 49

= 25x²y²- 49

Answer 2

`(5xy + 7)(5xy-7) = 25x^2 y^2 - 49`

Explanation:

`(a - b)(a +b ) = a^2 - b^2 \\\\From \ given \ expression \ a = 5xy \ , \ b = 7\\\\Therefore , (5xy + 7 )(5xy - 7 ) = ( 5xy)^2 - ( 7)^2 \\`

`= 25x^2 y^2 - 49`