How do you solve #2x ^ { 2} - 2x - 10= 0#?

1 Answer
Apr 6, 2017

#x=(1+-sqrt(21))/2#

Explanation:

If
#color(white)("XXX")2x^2-2x-10=0#
then (after dividing both sides by 2)
#color(white)("XXX")x^2-x-5=0#

Applying the quadratic formula
#color(white)("XXX")x=(1+-sqrt((-1)^2+4 * 1 * (-5)))/(2 * 1)#

#color(white)("XXxX")=(1+-sqrt(21))/2#