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272x^{2}-192x+108=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.
x=\frac{-\left(-192\right)±\sqrt{\left(-192\right)^{2}-4\times 272\times 108}}{2\times 272}
This equation is in standard form: ax^{2}+bx+c=0. Substitute 272 for a, -192 for b, and 108 for c in the quadratic formula, \frac{-b±\sqrt{b^{2}-4ac}}{2a}.
x=\frac{-\left(-192\right)±\sqrt{36864-4\times 272\times 108}}{2\times 272}
Square -192.
x=\frac{-\left(-192\right)±\sqrt{36864-1088\times 108}}{2\times 272}
Multiply -4 times 272.
x=\frac{-\left(-192\right)±\sqrt{36864-117504}}{2\times 272}
Multiply -1088 times 108.
x=\frac{-\left(-192\right)±\sqrt{-80640}}{2\times 272}
Add 36864 to -117504.
x=\frac{-\left(-192\right)±48\sqrt{35}i}{2\times 272}
Take the square root of -80640.
x=\frac{192±48\sqrt{35}i}{2\times 272}
The opposite of -192 is 192.
x=\frac{192±48\sqrt{35}i}{544}
Multiply 2 times 272.
x=\frac{192+48\sqrt{35}i}{544}
Now solve the equation x=\frac{192±48\sqrt{35}i}{544} when ± is plus. Add 192 to 48i\sqrt{35}.
x=\frac{3\sqrt{35}i}{34}+\frac{6}{17}
Divide 192+48i\sqrt{35} by 544.
x=\frac{-48\sqrt{35}i+192}{544}
Now solve the equation x=\frac{192±48\sqrt{35}i}{544} when ± is minus. Subtract 48i\sqrt{35} from 192.
x=-\frac{3\sqrt{35}i}{34}+\frac{6}{17}
Divide 192-48i\sqrt{35} by 544.
x=\frac{3\sqrt{35}i}{34}+\frac{6}{17} x=-\frac{3\sqrt{35}i}{34}+\frac{6}{17}
The equation is now solved.
272x^{2}-192x+108=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.
272x^{2}-192x+108-108=-108
Subtract 108 from both sides of the equation.
272x^{2}-192x=-108
Subtracting 108 from itself leaves 0.
\frac{272x^{2}-192x}{272}=-\frac{108}{272}
Divide both sides by 272.
x^{2}+\left(-\frac{192}{272}\right)x=-\frac{108}{272}
Dividing by 272 undoes the multiplication by 272.
x^{2}-\frac{12}{17}x=-\frac{108}{272}
Reduce the fraction \frac{-192}{272} to lowest terms by extracting and canceling out 16.
x^{2}-\frac{12}{17}x=-\frac{27}{68}
Reduce the fraction \frac{-108}{272} to lowest terms by extracting and canceling out 4.
x^{2}-\frac{12}{17}x+\left(-\frac{6}{17}\right)^{2}=-\frac{27}{68}+\left(-\frac{6}{17}\right)^{2}
Divide -\frac{12}{17}, the coefficient of the x term, by 2 to get -\frac{6}{17}. Then add the square of -\frac{6}{17} to both sides of the equation. This step makes the left hand side of the equation a perfect square.
x^{2}-\frac{12}{17}x+\frac{36}{289}=-\frac{27}{68}+\frac{36}{289}
Square -\frac{6}{17} by squaring both the numerator and the denominator of the fraction.
x^{2}-\frac{12}{17}x+\frac{36}{289}=-\frac{315}{1156}
Add -\frac{27}{68} to \frac{36}{289} by finding a common denominator and adding the numerators. Then reduce the fraction to lowest terms if possible.
\left(x-\frac{6}{17}\right)^{2}=-\frac{315}{1156}
Factor x^{2}-\frac{12}{17}x+\frac{36}{289}. 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(x-\frac{6}{17}\right)^{2}}=\sqrt{-\frac{315}{1156}}
Take the square root of both sides of the equation.
x-\frac{6}{17}=\frac{3\sqrt{35}i}{34} x-\frac{6}{17}=-\frac{3\sqrt{35}i}{34}
Simplify.
x=\frac{3\sqrt{35}i}{34}+\frac{6}{17} x=-\frac{3\sqrt{35}i}{34}+\frac{6}{17}
Add \frac{6}{17} to both sides of the equation.
x ^ 2 -\frac{12}{17}x +\frac{27}{68} = 0
Quadratic equations such as this one can be solved by a new direct factoring method that does not require guess work. To use the direct factoring method, the equation must be in the form x^2+Bx+C=0.This is achieved by dividing both sides of the equation by 272
r + s = \frac{12}{17} rs = \frac{27}{68}
Let r and s be the factors for the quadratic equation such that x^2+Bx+C=(x−r)(x−s) where sum of factors (r+s)=−B and the product of factors rs = C
r = \frac{6}{17} - u s = \frac{6}{17} + u
Two numbers r and s sum up to \frac{12}{17} exactly when the average of the two numbers is \frac{1}{2}*\frac{12}{17} = \frac{6}{17}. You can also see that the midpoint of r and s corresponds to the axis of symmetry of the parabola represented by the quadratic equation y=x^2+Bx+C. The values of r and s are equidistant from the center by an unknown quantity u. Express r and s with respect to variable u. <div style='padding: 8px'><img src='https://opalmath.azureedge.net/customsolver/quadraticgraph.png' style='width: 100%;max-width: 700px' /></div>
(\frac{6}{17} - u) (\frac{6}{17} + u) = \frac{27}{68}
To solve for unknown quantity u, substitute these in the product equation rs = \frac{27}{68}
\frac{36}{289} - u^2 = \frac{27}{68}
Simplify by expanding (a -b) (a + b) = a^2 – b^2
-u^2 = \frac{27}{68}-\frac{36}{289} = \frac{315}{1156}
Simplify the expression by subtracting \frac{36}{289} on both sides
u^2 = -\frac{315}{1156} u = \pm\sqrt{-\frac{315}{1156}} = \pm \frac{\sqrt{315}}{34}i
Simplify the expression by multiplying -1 on both sides and take the square root to obtain the value of unknown variable u
r =\frac{6}{17} - \frac{\sqrt{315}}{34}i = 0.353 - 0.522i s = \frac{6}{17} + \frac{\sqrt{315}}{34}i = 0.353 + 0.522i
The factors r and s are the solutions to the quadratic equation. Substitute the value of u to compute the r and s.