X^2+7x+7=0 use the quadratic formula to solve the equation?

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Answer 1 · 2018-04-22T03:40:45

See below

#x^2+7x+7=0#

Standard form of quadratic equation:
#ax^2+bx+c#

Therefore in this equation:
#a=1#
#b=7#
#c=7#

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

Plug in givens and solve:
#x=(-7+-sqrt((7)^2-4(1)(7)))/(2*1)#

#x=(-7+-sqrt(49-28))/(2)#

#x=(-7+-sqrt(21))/(2)#

#x=-7/2+sqrt(21)/2#
#x=-7/2-sqrt(21)/2#

#xapprox-1.209#
#xapprox-5.791#

graph{x^2+7x+7 [-10, 10, -5, 5]}