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

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Answer 1 · 2015-05-24T16:56:16

$y = 5 (n^{2} + 19 \frac{n}{5} - \frac{66}{5})$ $y = 5(n^2 + 19n/5 - 66/5)$

$(n^{2} + 19 \frac{n}{5} + {(\frac{19}{10})}^{2} - {(\frac{19}{10})}^{2} - \frac{66}{5})$ $(n^2 + 19n/5 + (19/10)^2 - (19/10)^2 - 66/5)$ = 0

${(n + \frac{19}{10})}^{2} = \frac{361 + 132}{10})$ $(n + 19/10)^2 = (361 + 132)/10)$

${(n + \frac{19}{10})}^{2} = \frac{493}{10} = 4.93$ $(n + 19/10)^2 = 493/10 = 4.93$

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

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

How do you solve 5n2+19n−68=−25n^2 + 19n - 68 = -2 by completing the square?