回答: #y = 7(x-2)^ 2-13# 説明: #y = 7x ^ 2-14x-6# #y + 6 = 7 x ^ 2〜14 x# #y + 6 = 7(x ^ 2-2x)# #y + 6 + 7 c = 7(x ^ 2-2 x + c)# #c =( - 2/2)^ 2 = 1# #y + 6 + 7 * 1 = 7(x ^ 2-2x + 1)# #y + 13 = 7(x-2)^ 2# #y = 7(x-2)^ 2-13#