Solve for x
x=-1
x=\frac{10}{13}\approx 0.769230769
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2x=\left(x-2\right)\times 5+13x^{2}
Variable x cannot be equal to 2 since division by zero is not defined. Multiply both sides of the equation by x-2.
2x=5x-10+13x^{2}
Use the distributive property to multiply x-2 by 5.
2x-5x=-10+13x^{2}
Subtract 5x from both sides.
-3x=-10+13x^{2}
Combine 2x and -5x to get -3x.
-3x-\left(-10\right)=13x^{2}
Subtract -10 from both sides.
-3x+10=13x^{2}
The opposite of -10 is 10.
-3x+10-13x^{2}=0
Subtract 13x^{2} from both sides.
-13x^{2}-3x+10=0
Rearrange the polynomial to put it in standard form. Place the terms in order from highest to lowest power.
a+b=-3 ab=-13\times 10=-130
To solve the equation, factor the left hand side by grouping. First, left hand side needs to be rewritten as -13x^{2}+ax+bx+10. To find a and b, set up a system to be solved.
1,-130 2,-65 5,-26 10,-13
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 -130.
1-130=-129 2-65=-63 5-26=-21 10-13=-3
Calculate the sum for each pair.
a=10 b=-13
The solution is the pair that gives sum -3.
\left(-13x^{2}+10x\right)+\left(-13x+10\right)
Rewrite -13x^{2}-3x+10 as \left(-13x^{2}+10x\right)+\left(-13x+10\right).
-x\left(13x-10\right)-\left(13x-10\right)
Factor out -x in the first and -1 in the second group.
\left(13x-10\right)\left(-x-1\right)
Factor out common term 13x-10 by using distributive property.
x=\frac{10}{13} x=-1
To find equation solutions, solve 13x-10=0 and -x-1=0.
2x=\left(x-2\right)\times 5+13x^{2}
Variable x cannot be equal to 2 since division by zero is not defined. Multiply both sides of the equation by x-2.
2x=5x-10+13x^{2}
Use the distributive property to multiply x-2 by 5.
2x-5x=-10+13x^{2}
Subtract 5x from both sides.
-3x=-10+13x^{2}
Combine 2x and -5x to get -3x.
-3x-\left(-10\right)=13x^{2}
Subtract -10 from both sides.
-3x+10=13x^{2}
The opposite of -10 is 10.
-3x+10-13x^{2}=0
Subtract 13x^{2} from both sides.
-13x^{2}-3x+10=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\left(-13\right)\times 10}}{2\left(-13\right)}
This equation is in standard form: ax^{2}+bx+c=0. Substitute -13 for a, -3 for b, and 10 for c in the quadratic formula, \frac{-b±\sqrt{b^{2}-4ac}}{2a}.
x=\frac{-\left(-3\right)±\sqrt{9-4\left(-13\right)\times 10}}{2\left(-13\right)}
Square -3.
x=\frac{-\left(-3\right)±\sqrt{9+52\times 10}}{2\left(-13\right)}
Multiply -4 times -13.
x=\frac{-\left(-3\right)±\sqrt{9+520}}{2\left(-13\right)}
Multiply 52 times 10.
x=\frac{-\left(-3\right)±\sqrt{529}}{2\left(-13\right)}
Add 9 to 520.
x=\frac{-\left(-3\right)±23}{2\left(-13\right)}
Take the square root of 529.
x=\frac{3±23}{2\left(-13\right)}
The opposite of -3 is 3.
x=\frac{3±23}{-26}
Multiply 2 times -13.
x=\frac{26}{-26}
Now solve the equation x=\frac{3±23}{-26} when ± is plus. Add 3 to 23.
x=-1
Divide 26 by -26.
x=-\frac{20}{-26}
Now solve the equation x=\frac{3±23}{-26} when ± is minus. Subtract 23 from 3.
x=\frac{10}{13}
Reduce the fraction \frac{-20}{-26} to lowest terms by extracting and canceling out 2.
x=-1 x=\frac{10}{13}
The equation is now solved.
2x=\left(x-2\right)\times 5+13x^{2}
Variable x cannot be equal to 2 since division by zero is not defined. Multiply both sides of the equation by x-2.
2x=5x-10+13x^{2}
Use the distributive property to multiply x-2 by 5.
2x-5x=-10+13x^{2}
Subtract 5x from both sides.
-3x=-10+13x^{2}
Combine 2x and -5x to get -3x.
-3x-13x^{2}=-10
Subtract 13x^{2} from both sides.
-13x^{2}-3x=-10
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{-13x^{2}-3x}{-13}=-\frac{10}{-13}
Divide both sides by -13.
x^{2}+\left(-\frac{3}{-13}\right)x=-\frac{10}{-13}
Dividing by -13 undoes the multiplication by -13.
x^{2}+\frac{3}{13}x=-\frac{10}{-13}
Divide -3 by -13.
x^{2}+\frac{3}{13}x=\frac{10}{13}
Divide -10 by -13.
x^{2}+\frac{3}{13}x+\left(\frac{3}{26}\right)^{2}=\frac{10}{13}+\left(\frac{3}{26}\right)^{2}
Divide \frac{3}{13}, the coefficient of the x term, by 2 to get \frac{3}{26}. Then add the square of \frac{3}{26} to both sides of the equation. This step makes the left hand side of the equation a perfect square.
x^{2}+\frac{3}{13}x+\frac{9}{676}=\frac{10}{13}+\frac{9}{676}
Square \frac{3}{26} by squaring both the numerator and the denominator of the fraction.
x^{2}+\frac{3}{13}x+\frac{9}{676}=\frac{529}{676}
Add \frac{10}{13} to \frac{9}{676} by finding a common denominator and adding the numerators. Then reduce the fraction to lowest terms if possible.
\left(x+\frac{3}{26}\right)^{2}=\frac{529}{676}
Factor x^{2}+\frac{3}{13}x+\frac{9}{676}. 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}{26}\right)^{2}}=\sqrt{\frac{529}{676}}
Take the square root of both sides of the equation.
x+\frac{3}{26}=\frac{23}{26} x+\frac{3}{26}=-\frac{23}{26}
Simplify.
x=\frac{10}{13} x=-1
Subtract \frac{3}{26} from both sides of the equation.
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