How do you solve #x^2-8x+3=0# using the quadratic formula?

1 Answer
Kayla
Aug 22, 2016

#x = 7.605# and #x= 0.395#

Explanation:

I'll show the quadratic formula down below so we can use that as a reference:
www.showme.com

I think it's worthwhile to mention that #a# is the number that has the #x^2# term associated with it. Thus, it would be #1x^(2)# for this question.#b# is the number that has the #x# variable associated with it and it would be #-8x#, and #c# is a number by itself. It would be 3 for this question.

Now, we just plug our values into the equation like this:

#x = (- (-8) +- sqrt((-8)^(2) - 4(1)(3)))/(2(1))#

#x = (8 +-sqrt(64-12))/2#

#x = (8 +- 7.21)/2#

For these type of problems, you will obtain two solutions because of the #+-# part. So what you want to do is add 8 and 7.21 together and divide that by 2:

#x = (8+7.21)/2#
#x = 15.21/2= 7.605#

Now, we subtract 7.21 from 8 and divide by 2:

#x = (8-7.21)/2#
# x = 0.79/2 = 0.395#

Therefore, the two possible solutions are:
#x = 7.605# and #x = 0.395#

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