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x^{2}=1.2769-1.13x
Multiply 1.13 and 1.13 to get 1.2769.
x^{2}-1.2769=-1.13x
Subtract 1.2769 from both sides.
x^{2}-1.2769+1.13x=0
Add 1.13x to both sides.
x^{2}+1.13x-1.2769=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{-1.13±\sqrt{1.13^{2}-4\left(-1.2769\right)}}{2}
This equation is in standard form: ax^{2}+bx+c=0. Substitute 1 for a, 1.13 for b, and -1.2769 for c in the quadratic formula, \frac{-b±\sqrt{b^{2}-4ac}}{2a}.
x=\frac{-1.13±\sqrt{1.2769-4\left(-1.2769\right)}}{2}
Square 1.13 by squaring both the numerator and the denominator of the fraction.
x=\frac{-1.13±\sqrt{1.2769+5.1076}}{2}
Multiply -4 times -1.2769.
x=\frac{-1.13±\sqrt{6.3845}}{2}
Add 1.2769 to 5.1076 by finding a common denominator and adding the numerators. Then reduce the fraction to lowest terms if possible.
x=\frac{-1.13±\frac{113\sqrt{5}}{100}}{2}
Take the square root of 6.3845.
x=\frac{113\sqrt{5}-113}{2\times 100}
Now solve the equation x=\frac{-1.13±\frac{113\sqrt{5}}{100}}{2} when ± is plus. Add -1.13 to \frac{113\sqrt{5}}{100}.
x=\frac{113\sqrt{5}-113}{200}
Divide \frac{-113+113\sqrt{5}}{100} by 2.
x=\frac{-113\sqrt{5}-113}{2\times 100}
Now solve the equation x=\frac{-1.13±\frac{113\sqrt{5}}{100}}{2} when ± is minus. Subtract \frac{113\sqrt{5}}{100} from -1.13.
x=\frac{-113\sqrt{5}-113}{200}
Divide \frac{-113-113\sqrt{5}}{100} by 2.
x=\frac{113\sqrt{5}-113}{200} x=\frac{-113\sqrt{5}-113}{200}
The equation is now solved.
x^{2}=1.2769-1.13x
Multiply 1.13 and 1.13 to get 1.2769.
x^{2}+1.13x=1.2769
Add 1.13x to both sides.
x^{2}+1.13x+0.565^{2}=1.2769+0.565^{2}
Divide 1.13, the coefficient of the x term, by 2 to get 0.565. Then add the square of 0.565 to both sides of the equation. This step makes the left hand side of the equation a perfect square.
x^{2}+1.13x+0.319225=1.2769+0.319225
Square 0.565 by squaring both the numerator and the denominator of the fraction.
x^{2}+1.13x+0.319225=1.596125
Add 1.2769 to 0.319225 by finding a common denominator and adding the numerators. Then reduce the fraction to lowest terms if possible.
\left(x+0.565\right)^{2}=1.596125
Factor x^{2}+1.13x+0.319225. 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+0.565\right)^{2}}=\sqrt{1.596125}
Take the square root of both sides of the equation.
x+0.565=\frac{113\sqrt{5}}{200} x+0.565=-\frac{113\sqrt{5}}{200}
Simplify.
x=\frac{113\sqrt{5}-113}{200} x=\frac{-113\sqrt{5}-113}{200}
Subtract 0.565 from both sides of the equation.