Solve by completing the square 6x-x^2-7

Mathematics

2 answers:

Maru [420]3 years ago

5 0

Hi there!

The completed square is -(x - 3) ^2 + 2

Hope this helps !

densk [106]3 years ago

3 0

Answer:

$x=\{3+\sqrt 2,\:\:3-\sqrt 2\}$

Step-by-step explanation:

$6x-x^2-7=0\\x^2-6x +7=0\\x^2-2.3.x +3^2=3^2-7\\(x-3)^2=9-7\\\huge\boxed{(x-3)^2=2}...(square\: completed)\\x-3=\pm\sqrt{2} \\x=3+\pm\sqrt{2}\\\therefore x =3+\sqrt{2}\: or \: x =3-\sqrt{2}\\\therefore x =\{3+\sqrt{2},\:\:3-\sqrt{2}\}\\$

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enyata [817]

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