perkalian bentuk aljabar! a.(x+5) × (5×-1) b.(7-2x) × (2x-15) c.(8×-5) × (4x+10) d.(26x+9) × (13+2x) sertakan jalannya! tolong ya besok dikumpul

a.(x+5) × (5×-1)
=5x - x + 25 - 5
=4x + 20

b.(7-2x) × (2x-15)
= 14x - 105 - 4x² + 30x
= -4x² + 30x + 14x - 105
= -4x + 44x - 105

c.(8×-5) × (4x+10)
=32x² + 80x - 20x - 50
= 32x² + 60x - 50

d.(26x+9) × (13+2x)
=338x + 52x² + 117 + 18x
= 52x² + 356x + 117