Identify the quadratic equation: Identify the quadratic equation.The given quadratic equation is x2−18x+81=0. We need to find the values of x that satisfy this equation.
Factor the quadratic equation: Factor the quadratic equation.We need to find two numbers that multiply to 81 (the constant term) and add up to −18 (the coefficient of the x term). The numbers that satisfy these conditions are −9 and −9, since (−9)×(−9)=81 and (−9)+(−9)=−18.
Write the factored form: Write the factored form of the equation.Using the numbers found in Step 2, we can write the factored form of the equation as (x−9)(x−9)=0.
Solve for x using the factored form: Solve for x using the factored form.Set each factor equal to zero and solve for x:x−9=0Add 9 to both sides:x−9+9=0+9x=9Since both factors are the same, we only get one unique solution for x.
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