Question 62773: I need help trying to figure this one out. Please.
x2 – 4x – 5 = 0 Solve by factoring? Could you please help me figure this one out? Answer by uma(370) (Show Source):
You can put this solution on YOUR website! x^2 - 4x - 5 = 0
Here we need to find two numbers whose sum is -4 and whose product is -5.
Clearly the numbers are -5 and 1.
==> x^2 + x - 5x - 5 = 0 [splitting the middle term]
==> x(x+1) - 5(x+1) = 0 [taking out the common factor]
==> (x+1)(x-5) = 0
==> x + 1 = 0 or x - 5 = 0
==> x = -1 or x = 5
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