Placed the following quadratic in vertex form by completing the square and then state the coordinates of its vertex? Y=x^2+18x-12

y = (x + 9)² -93

vertex: (-9, -93)

Step-by-step explanation:

x² + 18x = 12

x² + 18x + 81 = 12 + 81

(x+9)² = 93

y = (x + 9)² -93

vertex: (-9, -93)

a_n = a_1 + (n - 1)d

the first term is 6.

the common difference d = ?

when you find d, replace n with 7 and d with the common difference to find your answer.

what is the question