How do you solve using the quadratic formula $2x^2 + 5x = -3$ ?

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Answer 1 · 2017-06-12T15:51:27

See a solution process below:

First, put this equation in standard form:

$2x^2 + 5x + color(red)(3) = -3 + color(red)(3)$

$2x^2 + 5x + 3 = 0$

For $ax^2 + bx + c = 0$ , the values of $x$ which are the solutions to the equation are given by:

$x = (-b +- sqrt(b^2 - 4ac))/(2a)$

Substituting $2$ for $a$ ; $5$ for $b$ and $3$ for $c$ gives:

$x = (-5 +- sqrt(5^2 - (4 * 2 * 3)))/(2 * 2)$

$x = (-5 +- sqrt(25 - 24))/4$

$x = (-5 +- sqrt(1))/4$

$x = (-5 +- 1)/4$

$x = (-5 - 1)/4$ or $x = (-5 + 1)/4$

$x = -6/4$ or $x = -4/4$

$x = -3/2$ or $x = -1$

How do you solve using the quadratic formula 2x^2 + 5x = -32x^2 + 5x = -3?