Identify Equation Type: Identify the type of equation. The equation x2=2x+1 is a quadratic equation in the form of ax2+bx+c=0.
Rewrite in Standard Form: Rewrite the equation in standard form by subtracting 2x and 1 from both sides to get x2−2x−1=0.
Factor or Use Quadratic Formula: Attempt to factor the quadratic equation, if possible. In this case, the equation x2−2x−1 does not factor nicely, so we will use the quadratic formula instead. The quadratic formula is x=2a−b±b2−4ac, where a=1, b=−2, and c=−1.
Calculate Discriminant: Calculate the discriminant, which is the part under the square root in the quadratic formula: b2−4ac. Here, it is (−2)2−4(1)(−1)=4+4=8.
Insert Values into Formula: Insert the values of a, b, and c into the quadratic formula to find the solutions for x. x=2⋅1−(−2)±(8)=22±(8).
Simplify Solutions: Simplify the solutions. Since 8=4⋅2=22, the solutions are x=22±22.
Final Simplification: Further simplify the solutions by dividing each term by 2. The final solutions are x=1±2.
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