How do you solve $5n^2 + 19n - 68 = -2$ by completing the square?

Question

2176 views around the world

You can reuse this answer
Creative Commons License

Answer 1 · 2015-05-24T16:56:16

$y = 5(n^2 + 19n/5 - 66/5)$

$(n^2 + 19n/5 + (19/10)^2 - (19/10)^2 - 66/5)$ = 0

$(n + 19/10)^2 = (361 + 132)/10)$

$(n + 19/10)^2 = 493/10 = 4.93$

$n + 1.9 = 2.22 --n = 2.22 - 1.9 = 0.32$

$n + 1.9 = -2.22 -> n = -2.22 - 1.9 = -4.12$

How do you solve 5n^2 + 19n - 68 = -25n^2 + 19n - 68 = -2 by completing the square?