Question

Solve the quadratics attached using the quadratic formula or completing the square


`n^2+9n+18`

Answer 1

n = -3 or n = -6

Explanation:

Solve for n over the real numbers:

n^2 + 9 n + 18 = 0

Subtract 18 from both sides:

n^2 + 9 n = -18

Add 81/4 to both sides:

n^2 + 9 n + 81/4 = 9/4

Write the left-hand side as a square:

(n + 9/2)^2 = 9/4

Take the square root of both sides:

n + 9/2 = 3/2 or n + 9/2 = -3/2

Subtract 9/2 from both sides:

n = -3 or n + 9/2 = -3/2

Subtract 9/2 from both sides:

Answer: n = -3 or n = -6