How do you solve $x^2+8x=-2$ using the quadratic formula?

Question

How do you solve $x^2+8x=-2$ using the quadratic formula?

2 Answers

Impact of this question

2933 views around the world

You can reuse this answer
Creative Commons License

Answer 1 · 2018-04-16T21:08:39

$x=-4+-sqrt14$

Explanation:

First add $2$ to each side so that the equation is in standard form: $y=ax^2+bx+c$ .

$x^2+8x+2=0$

The quadratic formula is $(-b+-sqrt(b^2-4ac))/(2a)$ .

Here, $a$ is $1$ , $b$ is $8$ , and $c$ is $2$ . Let's plug these numbers into the quadratic formula.

$(-8+-sqrt(8^2-4*1*2))/(2*1)$

$(-8+-sqrt(64-8))/2$

$(-8+-sqrt56)/2$

$(-8+-2sqrt14)/2$

$-4+-sqrt14$

$x=-4+-sqrt14$

Answer 2 · 2018-04-16T21:11:42

$x=-.258, -7.74$ Those are averaged btw

Explanation:

first move the two over to the right side
$x^2 +8x +2=0$
Now plug into quadratic formula knowing that a quadratic equation is just $ax^2 +bx +c=0$ and the quadratic formula is $x=(-b+-(√b^2-4ac))/(2a)$
$x=(-(8)+-(√(8)^2-4(1)(2)))/(2(1))$
$x=(-8+-(√64-8))/(2)$
$x=(-8+(√56))/2$ or $x=(-8-(√56))/2$
Which means $x=-.258, -7.74$

Science

Math

Humanities

... and beyond

How do you solve $x^2+8x=-2$ using the quadratic formula?

2 Answers

Explanation:

Explanation:

Related questions

Impact of this question

Science

Math

Humanities

... and beyond

How do you solve x^2+8x=-2x^2+8x=-2 using the quadratic formula?

2 Answers

Explanation:

Explanation:

Related questions

Impact of this question

How do you solve $x^2+8x=-2$ using the quadratic formula?