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6x²+6x-2=0 using completing square method​

User Lilie
by
6.6k points

1 Answer

2 votes

Answer: x = ±
( √(21)-3 )/(6)

Explanation:

Given equation. We are being asked to solve for x by completing the square.

6x² + 6x - 2 = 0

First, we will isolate the constant.

6x² + 6x = 2

Next, we will factor out a 6.

6(x² + x) = 2

Now, we will add and subtract (b/2)^2. Remember that this is being multiplied by 6 when we remove it from the parentheses.

6(x² + x +
(1)/(4)) -
(3)/(2) = 2

Then, we will add
(3)/(2) to both sides of the equation.

6(x² + x +
(1)/(4)) =
(7)/(2)

Now, we can divide both sides of the equation by 6.

x² + x +
(1)/(4) =
(7)/(12)

Next, factor.

(x +
(1)/(2))² =
(7)/(12)

Then, solve for x by taking the square root of both sides of the equation and isolating the x-variable.

x = ±
( √(21)-3 )/(6)

User RyanKim
by
7.0k points