How do you convert x(2) squared + 18x =-45? Thanks!!

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Answer 1 · 2018-05-11T13:02:26

#(x+3 ) (x +15 )#

Add #-45# to the LH side

#x^2 + 18x +45#

#(x+3 ) (x +15 )#

The reason I chose #15# because #15 * 3 = 45# and you need to get the middle part to be #18# so the two numbers that equal #45# must add up to #18#

Answer 2 · 2018-05-11T13:03:17

#x = -15# and #x = -3#

#x^2 + 18x = -45#

Move all to one side:
#x^2 + 18x + 45 = 0#

Factor by looking for 2 Numbers to Multiply to 45 and Add to 18:
#(x + 15)(x+3) = 0#

Set each Factor #=0# and solve for #x#:
#x + 15 = 0#
#x = -15#

#x + 3 = 0#
#x = -3#