Skip to main content
Solve for x
Tick mark Image
Graph

Similar Problems from Web Search

Share

x^{2}-63x+1=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(-63\right)±\sqrt{\left(-63\right)^{2}-4}}{2}
This equation is in standard form: ax^{2}+bx+c=0. Substitute 1 for a, -63 for b, and 1 for c in the quadratic formula, \frac{-b±\sqrt{b^{2}-4ac}}{2a}.
x=\frac{-\left(-63\right)±\sqrt{3969-4}}{2}
Square -63.
x=\frac{-\left(-63\right)±\sqrt{3965}}{2}
Add 3969 to -4.
x=\frac{63±\sqrt{3965}}{2}
The opposite of -63 is 63.
x=\frac{\sqrt{3965}+63}{2}
Now solve the equation x=\frac{63±\sqrt{3965}}{2} when ± is plus. Add 63 to \sqrt{3965}.
x=\frac{63-\sqrt{3965}}{2}
Now solve the equation x=\frac{63±\sqrt{3965}}{2} when ± is minus. Subtract \sqrt{3965} from 63.
x=\frac{\sqrt{3965}+63}{2} x=\frac{63-\sqrt{3965}}{2}
The equation is now solved.
x^{2}-63x+1=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.
x^{2}-63x+1-1=-1
Subtract 1 from both sides of the equation.
x^{2}-63x=-1
Subtracting 1 from itself leaves 0.
x^{2}-63x+\left(-\frac{63}{2}\right)^{2}=-1+\left(-\frac{63}{2}\right)^{2}
Divide -63, the coefficient of the x term, by 2 to get -\frac{63}{2}. Then add the square of -\frac{63}{2} to both sides of the equation. This step makes the left hand side of the equation a perfect square.
x^{2}-63x+\frac{3969}{4}=-1+\frac{3969}{4}
Square -\frac{63}{2} by squaring both the numerator and the denominator of the fraction.
x^{2}-63x+\frac{3969}{4}=\frac{3965}{4}
Add -1 to \frac{3969}{4}.
\left(x-\frac{63}{2}\right)^{2}=\frac{3965}{4}
Factor x^{2}-63x+\frac{3969}{4}. 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{63}{2}\right)^{2}}=\sqrt{\frac{3965}{4}}
Take the square root of both sides of the equation.
x-\frac{63}{2}=\frac{\sqrt{3965}}{2} x-\frac{63}{2}=-\frac{\sqrt{3965}}{2}
Simplify.
x=\frac{\sqrt{3965}+63}{2} x=\frac{63-\sqrt{3965}}{2}
Add \frac{63}{2} to both sides of the equation.