Question

find the following products:(5x+7y) (5x-7y)​

Answer 1

Answer:

$- 14y$

Step-by-step explanation:

5x-5x-7y-7y

$= - 14y$

Answer 2

Answer:

Given,

Find the Product of :-

(5x + 7y) × (5x - 7y)

To Find :-

Product of the Terms.

$\huge\sf\underline{Solution}$

To Find The Product of the Terms There are Two Methods To Solve This.

• Method 1.

As we Know That (a + b) × (a - b) = a² - b²

$\sf\implies$ (5x + 7y) × (5x - 7y) = (5x)² - (7y)²

= 25x² - 49y²

$\sf\therefore$ (5x + 7y) × (5x - 7y) = 25x² - 49y².

• Method 2.

This is The Normal Method of Multiplication.

$\sf\implies$ (5x + 7y) × (5x - 7y) = 5x(5x - 7y) + 7y (5x - 7y)

= 5x(5x) - 5x(7y) + 7y(5x) - 7y(7y)

= 25x² - 35xy + 35xy + 49y²

= 25x² - 49y²

$\sf\therefore$ (5x + 7y) × (5x - 7y) = 25x² - 49y².