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10xx-1=3x
Variable x cannot be equal to 0 since division by zero is not defined. Multiply both sides of the equation by x.
10x^{2}-1=3x
Multiply x and x to get x^{2}.
10x^{2}-1-3x=0
Subtract 3x from both sides.
10x^{2}-3x-1=0
Rearrange the polynomial to put it in standard form. Place the terms in order from highest to lowest power.
a+b=-3 ab=10\left(-1\right)=-10
To solve the equation, factor the left hand side by grouping. First, left hand side needs to be rewritten as 10x^{2}+ax+bx-1. To find a and b, set up a system to be solved.
1,-10 2,-5
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 -10.
1-10=-9 2-5=-3
Calculate the sum for each pair.
a=-5 b=2
The solution is the pair that gives sum -3.
\left(10x^{2}-5x\right)+\left(2x-1\right)
Rewrite 10x^{2}-3x-1 as \left(10x^{2}-5x\right)+\left(2x-1\right).
5x\left(2x-1\right)+2x-1
Factor out 5x in 10x^{2}-5x.
\left(2x-1\right)\left(5x+1\right)
Factor out common term 2x-1 by using distributive property.
x=\frac{1}{2} x=-\frac{1}{5}
To find equation solutions, solve 2x-1=0 and 5x+1=0.
10xx-1=3x
Variable x cannot be equal to 0 since division by zero is not defined. Multiply both sides of the equation by x.
10x^{2}-1=3x
Multiply x and x to get x^{2}.
10x^{2}-1-3x=0
Subtract 3x from both sides.
10x^{2}-3x-1=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(-3\right)±\sqrt{\left(-3\right)^{2}-4\times 10\left(-1\right)}}{2\times 10}
This equation is in standard form: ax^{2}+bx+c=0. Substitute 10 for a, -3 for b, and -1 for c in the quadratic formula, \frac{-b±\sqrt{b^{2}-4ac}}{2a}.
x=\frac{-\left(-3\right)±\sqrt{9-4\times 10\left(-1\right)}}{2\times 10}
Square -3.
x=\frac{-\left(-3\right)±\sqrt{9-40\left(-1\right)}}{2\times 10}
Multiply -4 times 10.
x=\frac{-\left(-3\right)±\sqrt{9+40}}{2\times 10}
Multiply -40 times -1.
x=\frac{-\left(-3\right)±\sqrt{49}}{2\times 10}
Add 9 to 40.
x=\frac{-\left(-3\right)±7}{2\times 10}
Take the square root of 49.
x=\frac{3±7}{2\times 10}
The opposite of -3 is 3.
x=\frac{3±7}{20}
Multiply 2 times 10.
x=\frac{10}{20}
Now solve the equation x=\frac{3±7}{20} when ± is plus. Add 3 to 7.
x=\frac{1}{2}
Reduce the fraction \frac{10}{20} to lowest terms by extracting and canceling out 10.
x=-\frac{4}{20}
Now solve the equation x=\frac{3±7}{20} when ± is minus. Subtract 7 from 3.
x=-\frac{1}{5}
Reduce the fraction \frac{-4}{20} to lowest terms by extracting and canceling out 4.
x=\frac{1}{2} x=-\frac{1}{5}
The equation is now solved.
10xx-1=3x
Variable x cannot be equal to 0 since division by zero is not defined. Multiply both sides of the equation by x.
10x^{2}-1=3x
Multiply x and x to get x^{2}.
10x^{2}-1-3x=0
Subtract 3x from both sides.
10x^{2}-3x=1
Add 1 to both sides. Anything plus zero gives itself.
\frac{10x^{2}-3x}{10}=\frac{1}{10}
Divide both sides by 10.
x^{2}-\frac{3}{10}x=\frac{1}{10}
Dividing by 10 undoes the multiplication by 10.
x^{2}-\frac{3}{10}x+\left(-\frac{3}{20}\right)^{2}=\frac{1}{10}+\left(-\frac{3}{20}\right)^{2}
Divide -\frac{3}{10}, the coefficient of the x term, by 2 to get -\frac{3}{20}. Then add the square of -\frac{3}{20} to both sides of the equation. This step makes the left hand side of the equation a perfect square.
x^{2}-\frac{3}{10}x+\frac{9}{400}=\frac{1}{10}+\frac{9}{400}
Square -\frac{3}{20} by squaring both the numerator and the denominator of the fraction.
x^{2}-\frac{3}{10}x+\frac{9}{400}=\frac{49}{400}
Add \frac{1}{10} to \frac{9}{400} by finding a common denominator and adding the numerators. Then reduce the fraction to lowest terms if possible.
\left(x-\frac{3}{20}\right)^{2}=\frac{49}{400}
Factor x^{2}-\frac{3}{10}x+\frac{9}{400}. 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{3}{20}\right)^{2}}=\sqrt{\frac{49}{400}}
Take the square root of both sides of the equation.
x-\frac{3}{20}=\frac{7}{20} x-\frac{3}{20}=-\frac{7}{20}
Simplify.
x=\frac{1}{2} x=-\frac{1}{5}
Add \frac{3}{20} to both sides of the equation.