How do you solve #x^2 + 8x + 16 = 9#?

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Answer 1 · 2017-02-27T06:47:19

#x=-1# or #x=-7#

#x^2+8x+16=9#

Subtract #9# from both sides.

#x^2+8x+7=0#

Factorise.

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

#x(x+7)+1(x+7)=0#

#(x+1)(x+7)=0#

#x+1=0# and #x+7=0#

#x=-1# and #x=-7#