How do you solve #2x^2 + 12x= 10 # using the quadratic formula?

1 Answer
May 9, 2017

#x=-3+-sqrt14#

Explanation:

first rearrange to the form#" "ax^2+bx+c=0#

we have

#2x^2+12x-10=0#

divide out any common factors to make it simpler to use.

#(2x^2+12x-10=0)-:2#

#=>x^2+6x-5=0#

the formula is

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

#a=1, b=6, c=-5#

#x=(-6+-sqrt(6^2-4xx1xx(-5)))/(2xx1)#

#x=(-6+-sqrt(36+20))/2#

#x=(-6+-sqrt56)/2#

#x=-6/2+-sqrt56/2#

#x=-6/2+-2sqrt14/2#

#:.x=-3+-sqrt14#