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2x-3-1=-2x+x^{2}
Subtract 1 from both sides.
2x-4=-2x+x^{2}
Subtract 1 from -3 to get -4.
2x-4+2x=x^{2}
Add 2x to both sides.
4x-4=x^{2}
Combine 2x and 2x to get 4x.
4x-4-x^{2}=0
Subtract x^{2} from both sides.
-x^{2}+4x-4=0
Rearrange the polynomial to put it in standard form. Place the terms in order from highest to lowest power.
a+b=4 ab=-\left(-4\right)=4
To solve the equation, factor the left hand side by grouping. First, left hand side needs to be rewritten as -x^{2}+ax+bx-4. To find a and b, set up a system to be solved.
1,4 2,2
Since ab is positive, a and b have the same sign. Since a+b is positive, a and b are both positive. List all such integer pairs that give product 4.
1+4=5 2+2=4
Calculate the sum for each pair.
a=2 b=2
The solution is the pair that gives sum 4.
\left(-x^{2}+2x\right)+\left(2x-4\right)
Rewrite -x^{2}+4x-4 as \left(-x^{2}+2x\right)+\left(2x-4\right).
-x\left(x-2\right)+2\left(x-2\right)
Factor out -x in the first and 2 in the second group.
\left(x-2\right)\left(-x+2\right)
Factor out common term x-2 by using distributive property.
x=2 x=2
To find equation solutions, solve x-2=0 and -x+2=0.
2x-3-1=-2x+x^{2}
Subtract 1 from both sides.
2x-4=-2x+x^{2}
Subtract 1 from -3 to get -4.
2x-4+2x=x^{2}
Add 2x to both sides.
4x-4=x^{2}
Combine 2x and 2x to get 4x.
4x-4-x^{2}=0
Subtract x^{2} from both sides.
-x^{2}+4x-4=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{-4±\sqrt{4^{2}-4\left(-1\right)\left(-4\right)}}{2\left(-1\right)}
This equation is in standard form: ax^{2}+bx+c=0. Substitute -1 for a, 4 for b, and -4 for c in the quadratic formula, \frac{-b±\sqrt{b^{2}-4ac}}{2a}.
x=\frac{-4±\sqrt{16-4\left(-1\right)\left(-4\right)}}{2\left(-1\right)}
Square 4.
x=\frac{-4±\sqrt{16+4\left(-4\right)}}{2\left(-1\right)}
Multiply -4 times -1.
x=\frac{-4±\sqrt{16-16}}{2\left(-1\right)}
Multiply 4 times -4.
x=\frac{-4±\sqrt{0}}{2\left(-1\right)}
Add 16 to -16.
x=-\frac{4}{2\left(-1\right)}
Take the square root of 0.
x=-\frac{4}{-2}
Multiply 2 times -1.
x=2
Divide -4 by -2.
2x-3+2x=1+x^{2}
Add 2x to both sides.
4x-3=1+x^{2}
Combine 2x and 2x to get 4x.
4x-3-x^{2}=1
Subtract x^{2} from both sides.
4x-x^{2}=1+3
Add 3 to both sides.
4x-x^{2}=4
Add 1 and 3 to get 4.
-x^{2}+4x=4
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{-x^{2}+4x}{-1}=\frac{4}{-1}
Divide both sides by -1.
x^{2}+\frac{4}{-1}x=\frac{4}{-1}
Dividing by -1 undoes the multiplication by -1.
x^{2}-4x=\frac{4}{-1}
Divide 4 by -1.
x^{2}-4x=-4
Divide 4 by -1.
x^{2}-4x+\left(-2\right)^{2}=-4+\left(-2\right)^{2}
Divide -4, the coefficient of the x term, by 2 to get -2. Then add the square of -2 to both sides of the equation. This step makes the left hand side of the equation a perfect square.
x^{2}-4x+4=-4+4
Square -2.
x^{2}-4x+4=0
Add -4 to 4.
\left(x-2\right)^{2}=0
Factor x^{2}-4x+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-2\right)^{2}}=\sqrt{0}
Take the square root of both sides of the equation.
x-2=0 x-2=0
Simplify.
x=2 x=2
Add 2 to both sides of the equation.
x=2
The equation is now solved. Solutions are the same.