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Solve x²+5x+6=0 by completing the square​

User Kayani
by
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1 Answer

3 votes

Answer:

x = -2

x= -3

Explanation:

x 2+5x+6=0

To solve the equation, factor x^2+5x+6 using formula x^2+(a+b)x+ab=(x+a)(x+b). To find a and b, set up a system to be solved.

a+b=5

ab=6

Since ab is positive, a and b have the same sign. Since a+b is positive, a and b are both positive. List all such integer pairs that give product 6.

1,6

2,3

Calculate the sum for each pair.

1+6=7

2+3=5

The solution is the pair that gives sum 5.

a=2

b=3

Rewrite factored expression (x+a)(x+b) using the obtained values.

(x+2)(x+3)

To find equation solutions, solve x+2=0 and x+3=0.

x=−2

x=−3

User Mysl
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