Solve for x
x=-2
x=\frac{1}{4}=0.25
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4x^{2}+4x+1-3=-3x
Subtract 3 from both sides.
4x^{2}+4x-2=-3x
Subtract 3 from 1 to get -2.
4x^{2}+4x-2+3x=0
Add 3x to both sides.
4x^{2}+7x-2=0
Combine 4x and 3x to get 7x.
a+b=7 ab=4\left(-2\right)=-8
To solve the equation, factor the left hand side by grouping. First, left hand side needs to be rewritten as 4x^{2}+ax+bx-2. To find a and b, set up a system to be solved.
-1,8 -2,4
Since ab is negative, a and b have the opposite signs. Since a+b is positive, the positive number has greater absolute value than the negative. List all such integer pairs that give product -8.
-1+8=7 -2+4=2
Calculate the sum for each pair.
a=-1 b=8
The solution is the pair that gives sum 7.
\left(4x^{2}-x\right)+\left(8x-2\right)
Rewrite 4x^{2}+7x-2 as \left(4x^{2}-x\right)+\left(8x-2\right).
x\left(4x-1\right)+2\left(4x-1\right)
Factor out x in the first and 2 in the second group.
\left(4x-1\right)\left(x+2\right)
Factor out common term 4x-1 by using distributive property.
x=\frac{1}{4} x=-2
To find equation solutions, solve 4x-1=0 and x+2=0.
4x^{2}+4x+1-3=-3x
Subtract 3 from both sides.
4x^{2}+4x-2=-3x
Subtract 3 from 1 to get -2.
4x^{2}+4x-2+3x=0
Add 3x to both sides.
4x^{2}+7x-2=0
Combine 4x and 3x to get 7x.
x=\frac{-7±\sqrt{7^{2}-4\times 4\left(-2\right)}}{2\times 4}
This equation is in standard form: ax^{2}+bx+c=0. Substitute 4 for a, 7 for b, and -2 for c in the quadratic formula, \frac{-b±\sqrt{b^{2}-4ac}}{2a}.
x=\frac{-7±\sqrt{49-4\times 4\left(-2\right)}}{2\times 4}
Square 7.
x=\frac{-7±\sqrt{49-16\left(-2\right)}}{2\times 4}
Multiply -4 times 4.
x=\frac{-7±\sqrt{49+32}}{2\times 4}
Multiply -16 times -2.
x=\frac{-7±\sqrt{81}}{2\times 4}
Add 49 to 32.
x=\frac{-7±9}{2\times 4}
Take the square root of 81.
x=\frac{-7±9}{8}
Multiply 2 times 4.
x=\frac{2}{8}
Now solve the equation x=\frac{-7±9}{8} when ± is plus. Add -7 to 9.
x=\frac{1}{4}
Reduce the fraction \frac{2}{8} to lowest terms by extracting and canceling out 2.
x=-\frac{16}{8}
Now solve the equation x=\frac{-7±9}{8} when ± is minus. Subtract 9 from -7.
x=-2
Divide -16 by 8.
x=\frac{1}{4} x=-2
The equation is now solved.
4x^{2}+4x+1+3x=3
Add 3x to both sides.
4x^{2}+7x+1=3
Combine 4x and 3x to get 7x.
4x^{2}+7x=3-1
Subtract 1 from both sides.
4x^{2}+7x=2
Subtract 1 from 3 to get 2.
\frac{4x^{2}+7x}{4}=\frac{2}{4}
Divide both sides by 4.
x^{2}+\frac{7}{4}x=\frac{2}{4}
Dividing by 4 undoes the multiplication by 4.
x^{2}+\frac{7}{4}x=\frac{1}{2}
Reduce the fraction \frac{2}{4} to lowest terms by extracting and canceling out 2.
x^{2}+\frac{7}{4}x+\left(\frac{7}{8}\right)^{2}=\frac{1}{2}+\left(\frac{7}{8}\right)^{2}
Divide \frac{7}{4}, the coefficient of the x term, by 2 to get \frac{7}{8}. Then add the square of \frac{7}{8} to both sides of the equation. This step makes the left hand side of the equation a perfect square.
x^{2}+\frac{7}{4}x+\frac{49}{64}=\frac{1}{2}+\frac{49}{64}
Square \frac{7}{8} by squaring both the numerator and the denominator of the fraction.
x^{2}+\frac{7}{4}x+\frac{49}{64}=\frac{81}{64}
Add \frac{1}{2} to \frac{49}{64} by finding a common denominator and adding the numerators. Then reduce the fraction to lowest terms if possible.
\left(x+\frac{7}{8}\right)^{2}=\frac{81}{64}
Factor x^{2}+\frac{7}{4}x+\frac{49}{64}. 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{7}{8}\right)^{2}}=\sqrt{\frac{81}{64}}
Take the square root of both sides of the equation.
x+\frac{7}{8}=\frac{9}{8} x+\frac{7}{8}=-\frac{9}{8}
Simplify.
x=\frac{1}{4} x=-2
Subtract \frac{7}{8} 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}