Question

Solve for x in the equation x^2+ 4x-4=8.

X = -6 or x = 2
X=-2+or-2sqrt2
x = -2 or x = 6
x=2+or-2sqrt2

Answer 1

x = -6 or x = 2

Explanation:

i got 100% on the quiz

Answer 2

x = -6 or x = 2

Explanation:

The given equation is:

`x^(2)+4x-4=8\\\\ x^2+4x-4-8=0\\\\ x^2+4x-12=0\\\\`

This is quadratic equation, so we can use the quadratic formula to find the roots of the equation i.e. the value of x that satisfy the given equation.

According to the quadratic formula, the two roots will be:

`x=\frac{-b \pm \sqrt{b^(2)-4ac}}{2a}`

Here,

a = coefficient of x² = 1

b = coefficient of x = 4

c = constant term = -12

Using these values, we get:

`x=(-4 \pm √((4)^2-4(1)(-12)))/(2(1))\\\\ x=(-4 \pm √(64))/(2)\\\\ x=(-4 \pm 8)/(2)\\\\ x = (-4-8)/(2) , x = (-4+8)/(2)\\\\ x=-6, x = 2`

Thus, the two values of x that satisfy the given equation are: -6 and 2. So 1st option gives the correct answer.