Solve the equation by completing the square. Round to the nearest hundredth if necessary.
x^2-x=25
(A)4.97, 5.02
(B)5.52, –4.52
(C)25.75, –24.75
(D)5.45, –4.45

Question

Solve the equation by completing the square. Round to the nearest hundredth if necessary.
x^2-x=25
(A)4.97, 5.02
(B)5.52, –4.52
(C)25.75, –24.75
(D)5.45, –4.45

whpalmer4 · Answer

Put your equation in the form $$ax^2 + bx =c$$Divide through by $a$ if $a \ne 1$

$$x^2-x = 25$$Now take half the coefficient of the $x$ term, square it, and add to both sides.  You can rewrite the left hand side as a perfect square $(x-\frac{1}{2})^2$ at this point.. Take the square root of both sides and solve for the two values of $x$ (remember the square root has a positive and a negative value!)

dan815 · Answer

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