(×+3)(×+7)= (4×+8)(×-6)= 20×(2×)=

(x+3)(x+7)
= x(x+7) + 3(x+7)
= x²+7x + 3x+21
= x² + 10x + 21

(4x+8)(x-6)
= 4x(x-6) + 8(x-6)
= 4x²-24x + 8x-48
= 4x² - 16x - 48

20x(2x)
= 40x²

Semoga membantu yaa^^

(x + 3) (x + 7)
= x² + 7x 3x + 21
= x² + 10x +21

(4x + 8) (x - 6)
= 4x² - 24x + 8x - 48
= 4x² - 16 x - 48

20x (2x) = 40x²

Maaf kalo jawabannya ada yang salah :)