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4 years ago

Rewrite the equation by completing the square. x^2 + 2x – 48 = 0

Mathematics

1 answer:

slamgirl [31]4 years ago

3 0

Answer:

(x+1)^2 = 49

x = 6 x = -8

Step-by-step explanation:

x^2 + 2x – 48 = 0

Add 48 to each side

x^2 + 2x =48

Take the coefficient of x

Divide by 2

2/2=1

Square it

1^2 =1

x^2 + 2x +1=48+1

x^2 +2x+1 = 49

(x+1)^2 = 49

Take the square root of each side

sqrt((x+1)^2) =±sqrt( 49)

x+1 = ±7

Subtract 1 from each side

x+1-1 = -1 ±7

x = -1+7 x = -1 -7

x = 6 x = -8

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