D=1<span>^ - 4*6*(-1)= 1+24=25
х1 = -1+5:12=1/3
х2=-1-5:12 = -1/2=-0,5
Ответ: -0,5; 1/3</span>
S₁₁ = (a₁ + a₁₁)*11/2
22 = (a₁ + 92)*11/2
a₁ + 92 = 4
a₁ = -88
a₁₁ = a₁ + 10d
92 = -88 + 10d
10d = 180
d = 18
А=(68,56-25,3):2=43,26/2=21,63в=2*(2,405+3,41)=2*5,815=11,63<span>а-в=21,63-11,63=10</span>