Solve x^2-2x+36=1086

$$x ^ { 2 } - 2 x + 36 = 1086$$

Solve for x

$$x=\sqrt{1051}+1\approx 33.419130155$$

$$x=1-\sqrt{1051}\approx -31.419130155$$

Steps Using the Quadratic Formula

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.

$$x^{2}-2x+36=1086$$

Subtract 1086 from both sides of the equation.

$$x^{2}-2x+36-1086=1086-1086$$

Subtracting 1086 from itself leaves 0.

$$x^{2}-2x+36-1086=0$$

Subtract 1086 from 36.

$$x^{2}-2x-1050=0$$

This equation is in standard form: ax^{2}+bx+c=0. Substitute 1 for a, -2 for b, and -1050 for c in the quadratic formula, \frac{-b±\sqrt{b^{2}-4ac}}{2a}.

$$x=\frac{-\left(-2\right)±\sqrt{\left(-2\right)^{2}-4\left(-1050\right)}}{2}$$

Square -2.

$$x=\frac{-\left(-2\right)±\sqrt{4-4\left(-1050\right)}}{2}$$

Multiply -4 times -1050.

$$x=\frac{-\left(-2\right)±\sqrt{4+4200}}{2}$$

Add 4 to 4200.

$$x=\frac{-\left(-2\right)±\sqrt{4204}}{2}$$

Take the square root of 4204.

$$x=\frac{-\left(-2\right)±2\sqrt{1051}}{2}$$

The opposite of -2 is 2.

$$x=\frac{2±2\sqrt{1051}}{2}$$

Now solve the equation x=\frac{2±2\sqrt{1051}}{2} when ± is plus. Add 2 to 2\sqrt{1051}.

$$x=\frac{2\sqrt{1051}+2}{2}$$

Divide 2+2\sqrt{1051} by 2.

$$x=\sqrt{1051}+1$$

Now solve the equation x=\frac{2±2\sqrt{1051}}{2} when ± is minus. Subtract 2\sqrt{1051} from 2.

$$x=\frac{2-2\sqrt{1051}}{2}$$

Divide 2-2\sqrt{1051} by 2.

$$x=1-\sqrt{1051}$$

The equation is now solved.

$$x=\sqrt{1051}+1 x=1-\sqrt{1051}$$

Steps for Completing the Square

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.

$$x^{2}-2x+36=1086$$

Subtract 36 from both sides of the equation.

$$x^{2}-2x+36-36=1086-36$$

Subtracting 36 from itself leaves 0.

$$x^{2}-2x=1086-36$$

Subtract 36 from 1086.

$$x^{2}-2x=1050$$

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.

$$x^{2}-2x+1=1050+1$$

Add 1050 to 1.

$$x^{2}-2x+1=1051$$

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}.

$$\left(x-1\right)^{2}=1051$$

Take the square root of both sides of the equation.

$$\sqrt{\left(x-1\right)^{2}}=\sqrt{1051}$$

Simplify.

$$x-1=\sqrt{1051} x-1=-\sqrt{1051}$$

Add 1 to both sides of the equation.

$$x=\sqrt{1051}+1 x=1-\sqrt{1051}$$