How do you solve $3x^2+5x=2$ by completing the square?

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Answer 1 · 2018-06-26T10:15:03

$color(violet)(x = -2, 1/3$

$3x^2 + 5x = 2$

$(sqrt(3x))^2 + 2 * sqrt3 * x * (5/ (2 *sqrt3)) = 2$

$(sqrt3 x)^2 + 2 * sqrt3 * x * (5/ (2 *sqrt3)) + (5/(2 sqrt3))^2 = 2 + (5/(2 sqrt3))^2$

$((sqrt3 x) + 5/(2 sqrt3))^2 = 2 + 25/12 = 49/12$

$((sqrt3 x) + 5/(2 sqrt3))^2 = (sqrt(49/12))^2$

$sqrt 3 x + 5/ (2 sqrt3) = +- 7/ (2 sqrt3)$

$sqrt3 x = (-5 +- 7) / (2 sqrt3)$

$x = (-5 +- 7) / 6 = -2, 1/3$

How do you solve 3x^2+5x=23x^2+5x=2 by completing the square?