D = b²-4ac = 23²-4•120 = 529-480 = 49
x = 23±7/2
x1 = 30/2 = 15
x2 = 8
Ответ:
Объяснение:
1)
(125b²)³/25b^4= (5³b²)³/5²b^4 =5^9b^6/5^2b^4=5^(9-2)b^(6-4)=
=5^7b²
2)
45x^14y^9/-27x^12(-y³)³= 45x^14y^9/27x^12y^9 =
=5/3 x^(14-12)y^(9-9)=5/3 x²y^0=5/3 x²*1=5/3 x²
3)
-32c^15(d^4)^5/24c^13d^17= -4c^15d^20/3c^13d^17=
=-4/3 c^(15-13)d^(20-17)=-4/3 c²d³
-11.401-23.17+4.401-10.83 = - 41
1
8x²-160x+800-11x²-110x-275+3x²+170x-1600=0
-100x=1075
x=-10,75
2
40+20x+2,5x²+175-7x²-295+4,5x²=0
20x=80
x=4