Question

1) (1-2а)(3а+1)
2) (5-х)(4-х)
3) (6м-3)(2-5м)

Answer 1

 1) (1-2a)(3a+1)= 3a+1-6a²-2a
2) (5-x)(4-x)=20-5x-4x+x²
3)(6m-3)(2-5m)=12m-30m²-6+5m

Answer 2

там -6+15m