How do you solve #2x^2-x= -5# using the quadratic formula?

1 Answer
Apr 26, 2016

Answer:

The solutions for the equation are:

#color(green)( x = (1+sqrt(-39))/4, color(green)( x = (1-sqrt(-39))/4#

Explanation:

#2x^2 - x = -5#

#2x^2 - x + 5 = 0#

The equation is of the form #color(blue)(ax^2+bx+c=0# where:
#a=2, b=-1, c=5#

The Discriminant is given by:

#Delta=b^2-4*a*c#

# = (-1)^2-(4* 2 * 5)#

# = 1 - 40 = - 39 #

The solutions are found using the formula
#x=(-b+-sqrtDelta)/(2*a)#

#x = (-(-1)+-sqrt(-39))/(2*2) = (1+-sqrt(-39))/4#

The solutions are:

  • #color(green)( x = (1+sqrt(-39))/4#

  • #color(green)( x = (1-sqrt(-39))/4#