tolong jawab nomor 8-15. pakai cara dan jawab yg benar. mks kak

9) ( 15x - 14y + 13z ) + ( - 30x - 45y + 15z )
= 15x - 30x - 14y - 45y + 13z + 15z
= - 15x - 59y + 28z

10) a) ( 15x - 14y + 13z ) - ( 5x - 4y + 7z )
= 15x - 5x - 14y + 4y + 13z - 7z
= 10x - 10y + 6z

b) ( 20p - 7q + 7 ) - ( 4p - 3q + 13 )
= 20p - 4p - 7q + 3q + 7 - 13
= 16p - 4q - 6

11) 5 ( 2 + 3x - 2y )
= 10 + 15x - 10y

b) (2x + 1 )( 15x - 14y - 3 )
= 30x² + 15x - 28xy - 14y - 6x - 3

13) x² + 7x + 10
------------------------
( x + 2 )

= ( x + 2 )( x + 5 )
-------------------------
( x + 2 )

= x + 5

14) ( 2x + 5 )( 3x + 3 )
= 6x² + 15x + 6x + 15
= 6x² + 21x + 15
a = 6 , b = 21 , c = 15
a + b + c = 6 + 21 + 15 = 42

15) K = ( 5x - 8) + ( 7x + 6 ) + ( x + 5 )
K = 5x + 7x + x - 8 + 6 + 5
K = (13x + 3 ) cm

maaf apabila.ada yang salh dan tidak di isi