Question 241028
The quadratic formula is {{{x=(-b+-sqrt(b^2-4ac))/(2a)}}}


In this case, x^2 +12x+35=0, a=1, b=12, and c=35.


{{{x=(-12+-sqrt(144-4*1*35))/(2*1)}}}

{{{x=(-12+-sqrt(144-140))/2}}}

{{{x=(-12+-sqrt(4))/2}}}

{{{x=(-12+-2)/2}}}
{{{x=(-12+2)/2}}} or {{{x=(-12-2)/2}}}
{{{x=-10/2=-5}}} or {{{x=-14/2=-7}}}


This problem can be checked by solving by FACTORING:
x^2 +12x+35=0
(x+5)(x+7)=0
x=-5 or x=-7


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Dr. Robert J. Rapalje, Retired
Seminole State College of Florida
Altamonte Springs Campus