D=16+4•3•4=64
X1=4+8/6=12/6=2
X2=4-8/6=-4/6=-2/3
Ответ: 2; -2/3
Ctg(-1845)=ctg(-1845+1440+360)=ctg(-45)=-1
12x-7y=2
4x-5y=6
4x-5y=6
y=0.8x-1.2
12x-7y=2
12x-7*(0.8x-1.2)=2
6.4x+8.4-2=0
6.4x+6.4=0
x=-6.4/6.4
x=-1
4x-5y=6
4*(-1)-5y=6
y=-10/5
y=-2
1111, 3231, 5556, 7863, 9537, 5738
3*(x^2+8*x+16)-10*x-32=0
3*x^2+24*x+48-10*x-32=0
3*x^2+14*x+16=0
D=14^2 - 4 * 3 * 16 = 4
x1 = (-14-2) / 3*2 = -2 2/3
<span>x2 = (-14+2) / 3*2 = -2</span>