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c^{2}-2c+\frac{3}{4}=0
All equations of the form ax^{2}+bx+c=0 can be solved using the quadratic formula: \frac{-b±\sqrt{b^{2}-4ac}}{2a}. The quadratic formula gives two solutions, one when ± is addition and one when it is subtraction.
c=\frac{-\left(-2\right)±\sqrt{\left(-2\right)^{2}-4\times \frac{3}{4}}}{2}
This equation is in standard form: ax^{2}+bx+c=0. Substitute 1 for a, -2 for b, and \frac{3}{4} for c in the quadratic formula, \frac{-b±\sqrt{b^{2}-4ac}}{2a}.
c=\frac{-\left(-2\right)±\sqrt{4-4\times \frac{3}{4}}}{2}
Square -2.
c=\frac{-\left(-2\right)±\sqrt{4-3}}{2}
Multiply -4 times \frac{3}{4}.
c=\frac{-\left(-2\right)±\sqrt{1}}{2}
Add 4 to -3.
c=\frac{-\left(-2\right)±1}{2}
Take the square root of 1.
c=\frac{2±1}{2}
The opposite of -2 is 2.
c=\frac{3}{2}
Now solve the equation c=\frac{2±1}{2} when ± is plus. Add 2 to 1.
c=\frac{1}{2}
Now solve the equation c=\frac{2±1}{2} when ± is minus. Subtract 1 from 2.
c=\frac{3}{2} c=\frac{1}{2}
The equation is now solved.
c^{2}-2c+\frac{3}{4}=0
Quadratic equations such as this one can be solved by completing the square. In order to complete the square, the equation must first be in the form x^{2}+bx=c.
c^{2}-2c+\frac{3}{4}-\frac{3}{4}=-\frac{3}{4}
Subtract \frac{3}{4} from both sides of the equation.
c^{2}-2c=-\frac{3}{4}
Subtracting \frac{3}{4} from itself leaves 0.
c^{2}-2c+1=-\frac{3}{4}+1
Divide -2, the coefficient of the x term, by 2 to get -1. Then add the square of -1 to both sides of the equation. This step makes the left hand side of the equation a perfect square.
c^{2}-2c+1=\frac{1}{4}
Add -\frac{3}{4} to 1.
\left(c-1\right)^{2}=\frac{1}{4}
Factor c^{2}-2c+1. In general, when x^{2}+bx+c is a perfect square, it can always be factored as \left(x+\frac{b}{2}\right)^{2}.
\sqrt{\left(c-1\right)^{2}}=\sqrt{\frac{1}{4}}
Take the square root of both sides of the equation.
c-1=\frac{1}{2} c-1=-\frac{1}{2}
Simplify.
c=\frac{3}{2} c=\frac{1}{2}
Add 1 to both sides of the equation.