How do you solve #x^2 + 5x + 4 = 0 #?

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Answer 1 · 2017-07-25T05:20:13

You would factorise the equation first into this form
#(x+k)(x+r) = 0#

To do this you ask yourself this

What times what equals to 4
#k*r=4#

And what adds together to get 5
#k + r=5#

#k=1#
#r=4#

#(x + 1)(x + 4) = 0#

#x = -1#
#x = -4#