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3 years ago

Solve by completing the square. x^2 + 4x – 1= 0

Mathematics

1 answer:

NNADVOKAT [17]3 years ago

8 0

Answer:

x = -2 ± sqrt(5)

Step-by-step explanation:

x^2 + 4x – 1= 0

Add 1 to each side

x^2 + 4x – 1+1= 0+1

x^2 +4x = 1

Take the coefficient of x

Divide by 2

4/2 =2

Square it

2^2=4

Add it to each side

x^2 +4x+4=1+4

(x+2)^2 = 5

Take the square root of each side

sqrt((x+2)^2 )=± sqrt(5)

x+2 = ± sqrt(5)

Subtract 2 from each side

x+2-2 = -2 ± sqrt(5)

x = -2 ± sqrt(5)

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Answer:

Therefore

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$WX=85\ unit\\\\XY=85\ unit\\\\WY=104\ unit$

Step-by-step explanation:

Given:

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Δ WXY is an Isosceles Triangle ..Given

WX ≅ XY ...........Given

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$WX=85\ unit\\\\XY=85\ unit\\\\WY=104\ unit$

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