X squared + 12x +3 = 7 solve by completing the square

x = -6 ± 2sqrt(10)

Step-by-step explanation:

x^2 + 12x+3 = 7

Subtract 3 from each side

x^2 +12x = 4

Take the coefficient of x

12

Divide by 2

12/2 = 6

Square it

6^2 =36

Add this to each side

x^2 +12x +36 = 4+36

(x+6)^2 = 40

Take the square root of each side

sqrt((x+6)^2) =± sqrt(40)

x+6 = ± sqrt(40)

x+6 = ± sqrt(4)sqrt(10)

x+6 =± 2sqrt(10)

Subtract 6 from each side

x+6-6 = -6 ± 2sqrt(10)

x = -6 ± 2sqrt(10)

(x + 6)² = 40 → x = ±2√10 - 6

Step-by-step explanation:

x²+12x+3=7 can be solved by completing the square

To do so we must first find the term we are adding to both sides of the equation by using

In this case, our b is 12, so plugging this into the formula we get

We first need to subtract the 3 from both sides of the equation to get x²+12x=4

We then can add the 36 to both sides of the equation: x² + 12x + 36 = 4 + 36 → x² +12x + 36 = 40

Now we are able to factor the left side of the equation to get (x + 6)² = 40

To solve for x we need to take the square root of both sides to get x + 6 = ±2√10

Then we need to subtract 6 from both sides to get x = ±2√10 - 6