Sail with the equation by completing the square x^2+8x=-3

Mathematics

1 answer:

maxonik [38]3 years ago

5 0

Answer:

The solutions are $x=-4(+/-)\sqrt{13}$

Step-by-step explanation:

we have

$x^{2} +8x=-3$

Complete the square. Remember to balance the equation by adding the same constants to each side

$x^{2} +8x+16=-3+16$

$x^{2} +8x+16=13$

Rewrite as perfect squares

$(x+4)^{2}=13$

square root both sides

$x+4=(+/-)\sqrt{13}$

$x=-4(+/-)\sqrt{13}$

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