|5n+1|=8

解

∣ 5 n + 1 ∣ = 8

n = - \frac{9}{5} or n = \frac{7}{5}

十進法表記

n = - 1.8, n = 1.4

解答ステップ

∣ 5 n + 1 ∣ = 8

絶対規則を適用する:

∣ u ∣ = a, a > 0

の場合は

u = a

u = - a

5 n + 1 = - 8 or 5 n + 1 = 8

5 n + 1 = - 8 or 5 n + 1 = 8

n = - \frac{9}{5} or n = \frac{7}{5}