Question

factorise 4x square - 9 y square​

Answer 1

(2x + 3y) (2x - 3y)

Step-by-step explanation:

To factorise -

4x² - 9y²

Solution -

4x² - 9y²

= (2×2x²) - (3×3y²)

= (2²x²) - (3²y²)

= (2x)² - (3y)²

= (2x + 3y) (2x - 3y)

[by the property a² - b² = (a+b)(a-b), where a = 2x, b = 3y]

So

4x² - 9y² = (2x + 3y) (2x - 3y)

More to know :-

properties you will use in some questions -

• (a+b)² = a² + 2ab + b²
• (a-b)² = a² - 2ab + b²
• a² - b² = (a + b) (a - b)
• a² + b² = (a+b)² - 2ab or (a-b)² + 2ab

hope it helps.