Verified answer

9x^2 - 16y^2

= (3x)^2 - (4y)^2

Recall that a^2 - b^2 = (a + b)(a - b). So, the above function becomes:

(3x + 4y)(3x - 4y)

Hope this helps.

9x^2 - 16y^2 = (3x)^2 - (4y)^2 = (3x - 4y)(3x + 4y)

(difference of squares)

9x^2-16y^2 = (3x)^2 - (4y)^2 { a^2 - b^2 = ( a+b )( a - b ) }

= ( 3x - 4y )( 3x + 4y )

I see a difference of squares here:

(3x-4y)(3x+4y)

Write this as: (3x)^2 - (4y)^2 = (3x-4y)(3x+4y)

(3x - 4y) * (3x + 4y)