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#