kurangkanlah 1. 7a + 14 dari 9a + 12 =..........? 2. 2x² + 15x - 18 dari 11x² - 17x + 24 =.......? 3. -5 (4y² - 2y +8) dari

-1. 7a+14-9a+12
=7a-9a+14+12
=-2a+26
2.-5(4y²-2y+8)- 4(7y²+6y-5)
=-20y²+10y-40-28y²+24y-20
=-20y²-28y²+10y+24y-40-20
=-48y²+34y-60
3.(9x-6y) -(5x-3y)
=9x-5x-6y-3y
=4x-9y

semoga membantu :-)

1. 9a + 12 - (7a +14)
= 9a + 12 - 7a - 14
= 9a - 7a + 12 - 14
= 2a - 2

2. 11x² - 17x + 24 - ( 2x² + 15x - 18 )
= 11x² - 17x + 24 - 2x² - 15x + 18
= 11x² - 2x² - 17x - 15x + 24 + 18
= 9x² - 32x + 32

3. 4(7y² + 6y - 5 ) - ( -5( 4y² - 2y + 8 ))
= 28y² + 24y - 20 - ( -20y² + 10y - 40 )
= 28y² + 24y - 20 + 20y² - 10y + 40
= 28y² + 20y² + 24y - 10y - 20 + 40
= 48y² + 14y + 30

4. ( 9x - 6y ) - ( 5x - 3y )
= 9x - 6y - 5x + 3y
= 9x - 5x - 6y + 3y
= 4x - 3y

maaf kalau salah, semoga membantu ^^