(9-y)(y+5)=9y+45-y²-5y=-y²+4y+45
(2-b)(b+3)= 2b+6-b²-3b=-b²-b+6
(d+3)(d+11)=d²+11d+3d+33=d²+14d+33
(4nm+3)×(nm-8)=(4nm+3)(mn-8)=4m²n²-32mn+3mn-34=4m²n²-29mn-24
(9-y)(y+5)=9y+45-y²-5y=-y²+4y+45
(2-b)(b+3)= 2b+6-b²-3b=-b²-b+6
(d+3)(d+11)=d²+11d+3d+33=d²+14d+33
(4nm+3)×(nm-8)=(4nm+3)(mn-8)=4m²n²-32mn+3mn-34=4m²n²-29mn-24