Solve for x
x=\frac{1}{4}=0.25
x=-2
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-\left(5x-1\right)\times 2=\left(4x-3\right)x
Variable x cannot be equal to any of the values \frac{1}{5},\frac{3}{4} since division by zero is not defined. Multiply both sides of the equation by \left(4x-3\right)\left(5x-1\right), the least common multiple of 4x-3,5x-1.
-\left(10x-2\right)=\left(4x-3\right)x
Use the distributive property to multiply 5x-1 by 2.
-10x+2=\left(4x-3\right)x
To find the opposite of 10x-2, find the opposite of each term.
-10x+2=4x^{2}-3x
Use the distributive property to multiply 4x-3 by x.
-10x+2-4x^{2}=-3x
Subtract 4x^{2} from both sides.
-10x+2-4x^{2}+3x=0
Add 3x to both sides.
-7x+2-4x^{2}=0
Combine -10x and 3x to get -7x.
-4x^{2}-7x+2=0
Rearrange the polynomial to put it in standard form. Place the terms in order from highest to lowest power.
a+b=-7 ab=-4\times 2=-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 negative, the negative number has greater absolute value than the positive. 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.
-\left(5x-1\right)\times 2=\left(4x-3\right)x
Variable x cannot be equal to any of the values \frac{1}{5},\frac{3}{4} since division by zero is not defined. Multiply both sides of the equation by \left(4x-3\right)\left(5x-1\right), the least common multiple of 4x-3,5x-1.
-\left(10x-2\right)=\left(4x-3\right)x
Use the distributive property to multiply 5x-1 by 2.
-10x+2=\left(4x-3\right)x
To find the opposite of 10x-2, find the opposite of each term.
-10x+2=4x^{2}-3x
Use the distributive property to multiply 4x-3 by x.
-10x+2-4x^{2}=-3x
Subtract 4x^{2} from both sides.
-10x+2-4x^{2}+3x=0
Add 3x to both sides.
-7x+2-4x^{2}=0
Combine -10x and 3x to get -7x.
-4x^{2}-7x+2=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{-\left(-7\right)±\sqrt{\left(-7\right)^{2}-4\left(-4\right)\times 2}}{2\left(-4\right)}
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{-\left(-7\right)±\sqrt{49-4\left(-4\right)\times 2}}{2\left(-4\right)}
Square -7.
x=\frac{-\left(-7\right)±\sqrt{49+16\times 2}}{2\left(-4\right)}
Multiply -4 times -4.
x=\frac{-\left(-7\right)±\sqrt{49+32}}{2\left(-4\right)}
Multiply 16 times 2.
x=\frac{-\left(-7\right)±\sqrt{81}}{2\left(-4\right)}
Add 49 to 32.
x=\frac{-\left(-7\right)±9}{2\left(-4\right)}
Take the square root of 81.
x=\frac{7±9}{2\left(-4\right)}
The opposite of -7 is 7.
x=\frac{7±9}{-8}
Multiply 2 times -4.
x=\frac{16}{-8}
Now solve the equation x=\frac{7±9}{-8} when ± is plus. Add 7 to 9.
x=-2
Divide 16 by -8.
x=-\frac{2}{-8}
Now solve the equation x=\frac{7±9}{-8} when ± is minus. Subtract 9 from 7.
x=\frac{1}{4}
Reduce the fraction \frac{-2}{-8} to lowest terms by extracting and canceling out 2.
x=-2 x=\frac{1}{4}
The equation is now solved.
-\left(5x-1\right)\times 2=\left(4x-3\right)x
Variable x cannot be equal to any of the values \frac{1}{5},\frac{3}{4} since division by zero is not defined. Multiply both sides of the equation by \left(4x-3\right)\left(5x-1\right), the least common multiple of 4x-3,5x-1.
-\left(10x-2\right)=\left(4x-3\right)x
Use the distributive property to multiply 5x-1 by 2.
-10x+2=\left(4x-3\right)x
To find the opposite of 10x-2, find the opposite of each term.
-10x+2=4x^{2}-3x
Use the distributive property to multiply 4x-3 by x.
-10x+2-4x^{2}=-3x
Subtract 4x^{2} from both sides.
-10x+2-4x^{2}+3x=0
Add 3x to both sides.
-7x+2-4x^{2}=0
Combine -10x and 3x to get -7x.
-7x-4x^{2}=-2
Subtract 2 from both sides. Anything subtracted from zero gives its negation.
-4x^{2}-7x=-2
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{-4x^{2}-7x}{-4}=-\frac{2}{-4}
Divide both sides by -4.
x^{2}+\left(-\frac{7}{-4}\right)x=-\frac{2}{-4}
Dividing by -4 undoes the multiplication by -4.
x^{2}+\frac{7}{4}x=-\frac{2}{-4}
Divide -7 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}