Plisss banget kakak kakak jawab yang di lingkari Makasih

1) 7 × a × 4b × 5a
= 7 × 4b × 5a²
= 140a²b

4) 8xz . 3y²z . (-4x²y)
= (-96x³y³z²)

6) - 6mx² . 2xy² . (-4my) . (-5m²xy²)
= - 360m⁴x^5y^5

8) 2a(7a² + 4b)
= 14a³ + 8ab

9) - 5p²(6p - 3q)
= - 30p³ + 15p²q

12) 5m²(2m² + 8m²n - 5mn²)
= 10m³ + 40m⁴n - 25m²n²

13a) k = 2 × (5x + 1)+(3x)
k = 2 × (8x + 1)
k = 16x + 1
13b) k = 2x + (2y + 4) + (4x + 1) + 3y
k = 6x + 5y + 5

14) (x + 4)(x + 15)
= x² + 4x + 15x + 60
= x ² + 19x + 60

16) (4x + 3)(5x - 2)
= 20x² + 15x - 8x - 6
= 20x² + 7x - 6

17) (8 - 5x)(9 - 5x)
= 72 - 45x - 40x + 25x²
= 25x² - 85x + 72