Solve by Completing the Square x^2-2x-4=0

Problem

x2−2*x−4=0

Solution

1. Isolate the constant term by adding 4 to both sides of the equation.

x2−2*x=4

2. Calculate the value needed to complete the square by taking half of the coefficient of x which is −2 and squaring it.

((−2)/2)2=(−1)2=1

3. Add this value to both sides of the equation to maintain equality.

x2−2*x+1=4+1

4. Factor the left side as a perfect square trinomial and simplify the right side.

(x−1)2=5

5. Take the square root of both sides, remembering to include both the positive and negative roots.

x−1=±√(,5)

6. Solve for x by adding 1 to both sides.

x=1±√(,5)

Final Answer

x=1±√(,5)

Want more problems? Check here!