x₁ = 6 x₃ = - 28
x₃ = x₁ + 2d
2d = x₃ - x₁ = - 28 - 6 = - 34
d = - 17
x₁₁ = x₁ + 10d = 6 + 10 * (- 17) = 6 - 170 = - 164
ответ : x₁₁ = - 164
x₁ = 6 x₃ = - 28
x₃ = x₁ + 2d
2d = x₃ - x₁ = - 28 - 6 = - 34
d = - 17
x₁₁ = x₁ + 10d = 6 + 10 * (- 17) = 6 - 170 = - 164
ответ : x₁₁ = - 164