<span>
1/7а²b*23m -2/7a²bm=1/7 a²bm(23 - 2) = 21:7 a²bm = 3a²bm</span>
<span /><span>5а²-2аb+6a-7ab-6a²-6a= -a² -9ab = -a(a +9b)</span>
<span>a=5 b= -1/9</span>
<span>-5(5 -9x1/9) = -20</span>
Ответ:
Объяснение:
1)
a) 3a²/b:b/b³=3a²/b*b³/b=3a²b³/b²=3a²b
b) -2x²/y :6x³/b²= -2x²/y*b²/6x³=-b²/3xy
B)9m/14n: 4m²/21n²=9m/14n*21n/4m²=(9*3n)/(2*4m)=27n/8m=3,375n/m
G) 12x²:6x/c=12x²*c/6x=2cx
2.
a) (x+y²)/(a-3b) : (x²-y²)/(2a-6b)=(x+y²)/(a-3b) * 2(a-3b)/(x²-y²)=2(x+y²)/(x²-y²)
b) (y-8)/(x²-4) : (2y-16)/(3x-6)=(y-8)/(x²-4)*(3x-6)/2(y-8)=3(x-2)/2(x-2)(x+2)= =3/2(x+2)
B) (c²-9)/(c²+6c+9) : (3-c)/(c+3)=(c²-9/(c+3)²* (c+3)/(3-c)= =(c-3)(c+3)/(c+3) *(-1/(c-3)=-1
Надеюсь, что тут всё понятно