What is x if #-4(x+2)^2+3x=-5#?

1 Answer
Roella W.
Jan 11, 2016

#x = -9/4# or # x=-1#

Explanation:

First expand the expression and move the #-5# to the left hand side, to get it into standard form
#-4(x^2+4x+4) +3x +5 = 0#
#-4x^2 -16x -16 +3x +5 = 0#
#-4x^2 -13x -9 = 0#
#-(4x^2 +13x+9)=0#
#4# and #9# add to give #13#, so the factors we need are #4&1# and #9&1#
#-(4x +9)(x+1) = 0#
#:. x = -9/4# or # x=-1#

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