Solve for x
x=-\frac{1}{5}=-0.2
x=-3
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4x^{2}-4x+1=\left(3x+2\right)^{2}
Use binomial theorem \left(a-b\right)^{2}=a^{2}-2ab+b^{2} to expand \left(2x-1\right)^{2}.
4x^{2}-4x+1=9x^{2}+12x+4
Use binomial theorem \left(a+b\right)^{2}=a^{2}+2ab+b^{2} to expand \left(3x+2\right)^{2}.
4x^{2}-4x+1-9x^{2}=12x+4
Subtract 9x^{2} from both sides.
-5x^{2}-4x+1=12x+4
Combine 4x^{2} and -9x^{2} to get -5x^{2}.
-5x^{2}-4x+1-12x=4
Subtract 12x from both sides.
-5x^{2}-16x+1=4
Combine -4x and -12x to get -16x.
-5x^{2}-16x+1-4=0
Subtract 4 from both sides.
-5x^{2}-16x-3=0
Subtract 4 from 1 to get -3.
a+b=-16 ab=-5\left(-3\right)=15
To solve the equation, factor the left hand side by grouping. First, left hand side needs to be rewritten as -5x^{2}+ax+bx-3. To find a and b, set up a system to be solved.
-1,-15 -3,-5
Since ab is positive, a and b have the same sign. Since a+b is negative, a and b are both negative. List all such integer pairs that give product 15.
-1-15=-16 -3-5=-8
Calculate the sum for each pair.
a=-1 b=-15
The solution is the pair that gives sum -16.
\left(-5x^{2}-x\right)+\left(-15x-3\right)
Rewrite -5x^{2}-16x-3 as \left(-5x^{2}-x\right)+\left(-15x-3\right).
-x\left(5x+1\right)-3\left(5x+1\right)
Factor out -x in the first and -3 in the second group.
\left(5x+1\right)\left(-x-3\right)
Factor out common term 5x+1 by using distributive property.
x=-\frac{1}{5} x=-3
To find equation solutions, solve 5x+1=0 and -x-3=0.
4x^{2}-4x+1=\left(3x+2\right)^{2}
Use binomial theorem \left(a-b\right)^{2}=a^{2}-2ab+b^{2} to expand \left(2x-1\right)^{2}.
4x^{2}-4x+1=9x^{2}+12x+4
Use binomial theorem \left(a+b\right)^{2}=a^{2}+2ab+b^{2} to expand \left(3x+2\right)^{2}.
4x^{2}-4x+1-9x^{2}=12x+4
Subtract 9x^{2} from both sides.
-5x^{2}-4x+1=12x+4
Combine 4x^{2} and -9x^{2} to get -5x^{2}.
-5x^{2}-4x+1-12x=4
Subtract 12x from both sides.
-5x^{2}-16x+1=4
Combine -4x and -12x to get -16x.
-5x^{2}-16x+1-4=0
Subtract 4 from both sides.
-5x^{2}-16x-3=0
Subtract 4 from 1 to get -3.
x=\frac{-\left(-16\right)±\sqrt{\left(-16\right)^{2}-4\left(-5\right)\left(-3\right)}}{2\left(-5\right)}
This equation is in standard form: ax^{2}+bx+c=0. Substitute -5 for a, -16 for b, and -3 for c in the quadratic formula, \frac{-b±\sqrt{b^{2}-4ac}}{2a}.
x=\frac{-\left(-16\right)±\sqrt{256-4\left(-5\right)\left(-3\right)}}{2\left(-5\right)}
Square -16.
x=\frac{-\left(-16\right)±\sqrt{256+20\left(-3\right)}}{2\left(-5\right)}
Multiply -4 times -5.
x=\frac{-\left(-16\right)±\sqrt{256-60}}{2\left(-5\right)}
Multiply 20 times -3.
x=\frac{-\left(-16\right)±\sqrt{196}}{2\left(-5\right)}
Add 256 to -60.
x=\frac{-\left(-16\right)±14}{2\left(-5\right)}
Take the square root of 196.
x=\frac{16±14}{2\left(-5\right)}
The opposite of -16 is 16.
x=\frac{16±14}{-10}
Multiply 2 times -5.
x=\frac{30}{-10}
Now solve the equation x=\frac{16±14}{-10} when ± is plus. Add 16 to 14.
x=-3
Divide 30 by -10.
x=\frac{2}{-10}
Now solve the equation x=\frac{16±14}{-10} when ± is minus. Subtract 14 from 16.
x=-\frac{1}{5}
Reduce the fraction \frac{2}{-10} to lowest terms by extracting and canceling out 2.
x=-3 x=-\frac{1}{5}
The equation is now solved.
4x^{2}-4x+1=\left(3x+2\right)^{2}
Use binomial theorem \left(a-b\right)^{2}=a^{2}-2ab+b^{2} to expand \left(2x-1\right)^{2}.
4x^{2}-4x+1=9x^{2}+12x+4
Use binomial theorem \left(a+b\right)^{2}=a^{2}+2ab+b^{2} to expand \left(3x+2\right)^{2}.
4x^{2}-4x+1-9x^{2}=12x+4
Subtract 9x^{2} from both sides.
-5x^{2}-4x+1=12x+4
Combine 4x^{2} and -9x^{2} to get -5x^{2}.
-5x^{2}-4x+1-12x=4
Subtract 12x from both sides.
-5x^{2}-16x+1=4
Combine -4x and -12x to get -16x.
-5x^{2}-16x=4-1
Subtract 1 from both sides.
-5x^{2}-16x=3
Subtract 1 from 4 to get 3.
\frac{-5x^{2}-16x}{-5}=\frac{3}{-5}
Divide both sides by -5.
x^{2}+\left(-\frac{16}{-5}\right)x=\frac{3}{-5}
Dividing by -5 undoes the multiplication by -5.
x^{2}+\frac{16}{5}x=\frac{3}{-5}
Divide -16 by -5.
x^{2}+\frac{16}{5}x=-\frac{3}{5}
Divide 3 by -5.
x^{2}+\frac{16}{5}x+\left(\frac{8}{5}\right)^{2}=-\frac{3}{5}+\left(\frac{8}{5}\right)^{2}
Divide \frac{16}{5}, the coefficient of the x term, by 2 to get \frac{8}{5}. Then add the square of \frac{8}{5} to both sides of the equation. This step makes the left hand side of the equation a perfect square.
x^{2}+\frac{16}{5}x+\frac{64}{25}=-\frac{3}{5}+\frac{64}{25}
Square \frac{8}{5} by squaring both the numerator and the denominator of the fraction.
x^{2}+\frac{16}{5}x+\frac{64}{25}=\frac{49}{25}
Add -\frac{3}{5} to \frac{64}{25} by finding a common denominator and adding the numerators. Then reduce the fraction to lowest terms if possible.
\left(x+\frac{8}{5}\right)^{2}=\frac{49}{25}
Factor x^{2}+\frac{16}{5}x+\frac{64}{25}. 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{8}{5}\right)^{2}}=\sqrt{\frac{49}{25}}
Take the square root of both sides of the equation.
x+\frac{8}{5}=\frac{7}{5} x+\frac{8}{5}=-\frac{7}{5}
Simplify.
x=-\frac{1}{5} x=-3
Subtract \frac{8}{5} from both sides of the equation.
Examples
Quadratic equation
{ x } ^ { 2 } - 4 x - 5 = 0
Trigonometry
4 \sin \theta \cos \theta = 2 \sin \theta
Linear equation
y = 3x + 4
Arithmetic
699 * 533
Matrix
\left[ \begin{array} { l l } { 2 } & { 3 } \\ { 5 } & { 4 } \end{array} \right] \left[ \begin{array} { l l l } { 2 } & { 0 } & { 3 } \\ { -1 } & { 1 } & { 5 } \end{array} \right]
Simultaneous equation
\left. \begin{cases} { 8x+2y = 46 } \\ { 7x+3y = 47 } \end{cases} \right.
Differentiation
\frac { d } { d x } \frac { ( 3 x ^ { 2 } - 2 ) } { ( x - 5 ) }
Integration
\int _ { 0 } ^ { 1 } x e ^ { - x ^ { 2 } } d x
Limits
\lim _{x \rightarrow-3} \frac{x^{2}-9}{x^{2}+2 x-3}