Question

Please answer my questions it's necessary.

Answer 1

hiii!!!

here's ur answer...

(i) given :- 3a² - 2ab - 5b²

= 3a² - ( 5ab - 3ab ) - 5b²

= 3a² - 5ab + 3ab - 5b²

= a ( 3a - 5b ) + b ( 3a - 5b )

= ( 3a - 5b ) ( a + b )

(ii) given :- 7x² + 4xy - 3y²

= 7x² + ( 7xy - 3xy ) - 3y²

= 7x² + 7xy - 3xy - 3y²

= 7x ( x + y ) - 3y ( x + y )

= ( x + y ) ( 7x - 3y )

(iii) given :- x² + 7xy - 18y²

= x² + ( 9xy - 2xy ) - 18y²

= x² + 9xy - 2xy - 18y²

= x ( x + 9y ) - 2y ( x + 9y )

= ( x + 9y ) ( x - 2y )

hope this helps..!!

Answer 2

Your answer is here

$1. \: 3a {}^{2} - 2ab - 5b {}^{2} \\ = 3a {}^{2} - ab(5 - 3) - 5b {}^{2} \\ = 3a {}^{2} - 5ab + 3ab - 5b {}^{2} \\ = a(3a - 5b) + b(3a - 5b) \\ = (3a - 5b)(a + b)$
I hope it will help you