1) -5x ( x-2 ) + ( x-3 ) ( x + 1 ) 2) 3a ( a+3 ) - ( 2 - a ) ( 3a- 4 )

Question

1) -5x ( x-2 ) + ( x-3 ) ( x + 1 )
2) 3a ( a+3 ) - ( 2 - a ) ( 3a- 4 )

Answer 1

-5x ( x-2 ) + ( x-3 ) ( x + 1 ) =-5x^2+10x+x^2-2x-3=-4x^2+8x-3

 

3a ( a+3 ) - ( 2 - a ) ( 3a- 4 )=3a^2+9a-6a+8+3a^2-4a=6a^2-a+8

Answer 2

-5х*2-10х+х*2+х-3х-3=-4х*2-12х-3
3а*2+6а-(6а-8-3а*2-4а)=3а*2+6а-6а+8+3а*2-4а=6а*2-4а+8
Надо ли решать через дискриминант?