How do you solve y^2+3y+2=0?

1 Answer
Oct 10, 2016

y=-1 or y=-2

Explanation:

To solve this equation first,we should factorize it.
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In this exercise we can't factorize using common factor nor applying
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Polynomial identities , so I will apply trial and error method instead.
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First: Factorize
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Trial and error method :
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X^2+SX+P=0
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if we can find two real numbers a and b whose sum is S and
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product is P then color(blue)(X^2+SX+P=0=(X+a)(X+b)
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In the given equation the polynomial
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y^2+3y+2 has
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S=3 and P=2
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So,
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color(blue)(y^2+3y+2=(y+2)(y+1))

second: solve

y^2+3y+2=0
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(y+2)(y+1)=0
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y+2=0rArry=-2
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Or
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y+1=0rArry=-1