Skip to main content
Solve for x
Tick mark Image
Graph

Similar Problems from Web Search

Share

x=1+\frac{x^{2}-26}{2}+1
Add -32 and 6 to get -26.
x=2+\frac{x^{2}-26}{2}
Add 1 and 1 to get 2.
x=2+\frac{1}{2}x^{2}-13
Divide each term of x^{2}-26 by 2 to get \frac{1}{2}x^{2}-13.
x=-11+\frac{1}{2}x^{2}
Subtract 13 from 2 to get -11.
x-\left(-11\right)=\frac{1}{2}x^{2}
Subtract -11 from both sides.
x+11=\frac{1}{2}x^{2}
The opposite of -11 is 11.
x+11-\frac{1}{2}x^{2}=0
Subtract \frac{1}{2}x^{2} from both sides.
-\frac{1}{2}x^{2}+x+11=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±\sqrt{1^{2}-4\left(-\frac{1}{2}\right)\times 11}}{2\left(-\frac{1}{2}\right)}
This equation is in standard form: ax^{2}+bx+c=0. Substitute -\frac{1}{2} for a, 1 for b, and 11 for c in the quadratic formula, \frac{-b±\sqrt{b^{2}-4ac}}{2a}.
x=\frac{-1±\sqrt{1-4\left(-\frac{1}{2}\right)\times 11}}{2\left(-\frac{1}{2}\right)}
Square 1.
x=\frac{-1±\sqrt{1+2\times 11}}{2\left(-\frac{1}{2}\right)}
Multiply -4 times -\frac{1}{2}.
x=\frac{-1±\sqrt{1+22}}{2\left(-\frac{1}{2}\right)}
Multiply 2 times 11.
x=\frac{-1±\sqrt{23}}{2\left(-\frac{1}{2}\right)}
Add 1 to 22.
x=\frac{-1±\sqrt{23}}{-1}
Multiply 2 times -\frac{1}{2}.
x=\frac{\sqrt{23}-1}{-1}
Now solve the equation x=\frac{-1±\sqrt{23}}{-1} when ± is plus. Add -1 to \sqrt{23}.
x=1-\sqrt{23}
Divide -1+\sqrt{23} by -1.
x=\frac{-\sqrt{23}-1}{-1}
Now solve the equation x=\frac{-1±\sqrt{23}}{-1} when ± is minus. Subtract \sqrt{23} from -1.
x=\sqrt{23}+1
Divide -1-\sqrt{23} by -1.
x=1-\sqrt{23} x=\sqrt{23}+1
The equation is now solved.
x=1+\frac{x^{2}-26}{2}+1
Add -32 and 6 to get -26.
x=2+\frac{x^{2}-26}{2}
Add 1 and 1 to get 2.
x=2+\frac{1}{2}x^{2}-13
Divide each term of x^{2}-26 by 2 to get \frac{1}{2}x^{2}-13.
x=-11+\frac{1}{2}x^{2}
Subtract 13 from 2 to get -11.
x-\frac{1}{2}x^{2}=-11
Subtract \frac{1}{2}x^{2} from both sides.
-\frac{1}{2}x^{2}+x=-11
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.
\frac{-\frac{1}{2}x^{2}+x}{-\frac{1}{2}}=-\frac{11}{-\frac{1}{2}}
Multiply both sides by -2.
x^{2}+\frac{1}{-\frac{1}{2}}x=-\frac{11}{-\frac{1}{2}}
Dividing by -\frac{1}{2} undoes the multiplication by -\frac{1}{2}.
x^{2}-2x=-\frac{11}{-\frac{1}{2}}
Divide 1 by -\frac{1}{2} by multiplying 1 by the reciprocal of -\frac{1}{2}.
x^{2}-2x=22
Divide -11 by -\frac{1}{2} by multiplying -11 by the reciprocal of -\frac{1}{2}.
x^{2}-2x+1=22+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.
x^{2}-2x+1=23
Add 22 to 1.
\left(x-1\right)^{2}=23
Factor x^{2}-2x+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(x-1\right)^{2}}=\sqrt{23}
Take the square root of both sides of the equation.
x-1=\sqrt{23} x-1=-\sqrt{23}
Simplify.
x=\sqrt{23}+1 x=1-\sqrt{23}
Add 1 to both sides of the equation.