Q. Rewrite the equation by completing the square.x2−x−20=0(x+□)2=□
Rearrange the equation:x2−x−20=0Rearrange the equation to the form x2+bx by moving the constant term to the right side of the equation.x2−x=20
Complete the square:x2−x=20To complete the square, add the square of half the coefficient of x to both sides of the equation. The coefficient of x is −1, so half of it is −21, and the square of −21 is 41.x2−x+(41)=20+(41)x2−x+(41)=480+41x2−x+(41)=481
Simplify the equation:x2−x+(41)=481The left side of the equation is now a perfect square, and can be written as (x−21)2.(x−21)2=481
Write in completed square form:(x−21)2=481This is the completed square form of the equation.
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