Question

9. Factorise of x²7x+ 12 is​

Answer 1

x²+7x+ 12

x²+4x+3x+ 12

=> x( x + 4)+3(x + 4)

=> (x + 3)(x+4)

=> x = -3

=> x = -4

Answer 2

x² + 7x + 12

= x² + 4x + 3x + 12 [ as factors of 12 which make +7 can be ( -4 and -3 ) and ( 4 and 3 )]

= x ( x + 4 ) + 3 ( x + 4 )

= ( x + 4 )( x + 3 )