How do you solve #5x^2+98=0# using the quadratic formula?

1 Answer
Sep 11, 2016

Answer:

You don't need the quadratic formula. But here goes:

Answer is:

Equation not valid in #RR#

Explanation:

Quadratic solving

#5x^2+98=0#

This is the same as:

#5x^2+0x+98=0#

For #a=5# #b=0# #c=98# :

#Δ=b^2-4*a*c=0^2-4*5*98=-1960#

Since #Δ<0# the equation in impossible inside #RR#.

Simpler solution

#5x^2+98=0#

#5x^2=-98#

#x^2=-98/5#

No real number can have a negative square, therefore the equation in impossible inside #RR#.