1) (x-4)(x+8)=x²+8x-4x+32=x²+4x+32
2) (x+5)(x+9)=x²+9x+5x+45=x²+14x+45
3) (2-a)(a+3)=2a+6-a²-3a=a²+a-6
4) (8a+3x)(1-4x)=8a-32ax+3x-12x²
5) (x-10)(x-6)=x²-6x-10x+60=x²-16x+60
#384
2)16-x^2+2xy+y2
4)m^2-14m+14-64=m^2-14m-50
6)x^6-4y^4=4y^2x^3+x^6
#385
2)25-a^2+14a+49=74-a^2+14a
1) a²+a²=4a²
2)x²+x²+x²=3x²
3)m5+m5+m5=3m²
4)bb+bb+bb=3bb=3b²
5)xxx+xxx=2xxx=2x³
6)aa+bbb+aa+bbb=2aa+2bbb=2a²+2b³=2(a²+b³)
7)3x²/2y3
Y=7-2x
X^2-7+2x=1
=> x^2+2x-8=0
D=4+32=36
X1= (-2+6)/2=2
X2=(-2-6)/2=-4
y1=7-2*2=3
y2=7-2*(-4)=15
Ответ:(2;3)^(-4;15)