Solve for a
a = \frac{\sqrt{73} + 19}{18} \approx 1.53022243
a=\frac{19-\sqrt{73}}{18}\approx 0.580888681
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2\times 4+2a\left(-2\right)+a\left(2-a\right)\times \frac{2}{a-1}=3a
Variable a cannot be equal to 0 since division by zero is not defined. Multiply both sides of the equation by 2a, the least common multiple of a,2.
8+2a\left(-2\right)+a\left(2-a\right)\times \frac{2}{a-1}=3a
Multiply 2 and 4 to get 8.
8-4a+a\left(2-a\right)\times \frac{2}{a-1}=3a
Multiply 2 and -2 to get -4.
8-4a+\frac{a\times 2}{a-1}\left(2-a\right)=3a
Express a\times \frac{2}{a-1} as a single fraction.
8-4a+2\times \frac{a\times 2}{a-1}-\frac{a\times 2}{a-1}a=3a
Use the distributive property to multiply \frac{a\times 2}{a-1} by 2-a.
8-4a+\frac{2a\times 2}{a-1}-\frac{a\times 2}{a-1}a=3a
Express 2\times \frac{a\times 2}{a-1} as a single fraction.
8-4a+\frac{2a\times 2}{a-1}-\frac{a\times 2a}{a-1}=3a
Express \frac{a\times 2}{a-1}a as a single fraction.
8-4a+\frac{2a\times 2-a\times 2a}{a-1}=3a
Since \frac{2a\times 2}{a-1} and \frac{a\times 2a}{a-1} have the same denominator, subtract them by subtracting their numerators.
8-4a+\frac{4a-2a^{2}}{a-1}=3a
Do the multiplications in 2a\times 2-a\times 2a.
\frac{\left(8-4a\right)\left(a-1\right)}{a-1}+\frac{4a-2a^{2}}{a-1}=3a
To add or subtract expressions, expand them to make their denominators the same. Multiply 8-4a times \frac{a-1}{a-1}.
\frac{\left(8-4a\right)\left(a-1\right)+4a-2a^{2}}{a-1}=3a
Since \frac{\left(8-4a\right)\left(a-1\right)}{a-1} and \frac{4a-2a^{2}}{a-1} have the same denominator, add them by adding their numerators.
\frac{8a-8-4a^{2}+4a+4a-2a^{2}}{a-1}=3a
Do the multiplications in \left(8-4a\right)\left(a-1\right)+4a-2a^{2}.
\frac{16a-8-6a^{2}}{a-1}=3a
Combine like terms in 8a-8-4a^{2}+4a+4a-2a^{2}.
\frac{16a-8-6a^{2}}{a-1}-3a=0
Subtract 3a from both sides.
\frac{16a-8-6a^{2}}{a-1}+\frac{-3a\left(a-1\right)}{a-1}=0
To add or subtract expressions, expand them to make their denominators the same. Multiply -3a times \frac{a-1}{a-1}.
\frac{16a-8-6a^{2}-3a\left(a-1\right)}{a-1}=0
Since \frac{16a-8-6a^{2}}{a-1} and \frac{-3a\left(a-1\right)}{a-1} have the same denominator, add them by adding their numerators.
\frac{16a-8-6a^{2}-3a^{2}+3a}{a-1}=0
Do the multiplications in 16a-8-6a^{2}-3a\left(a-1\right).
\frac{19a-8-9a^{2}}{a-1}=0
Combine like terms in 16a-8-6a^{2}-3a^{2}+3a.
19a-8-9a^{2}=0
Variable a cannot be equal to 1 since division by zero is not defined. Multiply both sides of the equation by a-1.
-9a^{2}+19a-8=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.
a=\frac{-19±\sqrt{19^{2}-4\left(-9\right)\left(-8\right)}}{2\left(-9\right)}
This equation is in standard form: ax^{2}+bx+c=0. Substitute -9 for a, 19 for b, and -8 for c in the quadratic formula, \frac{-b±\sqrt{b^{2}-4ac}}{2a}.
a=\frac{-19±\sqrt{361-4\left(-9\right)\left(-8\right)}}{2\left(-9\right)}
Square 19.
a=\frac{-19±\sqrt{361+36\left(-8\right)}}{2\left(-9\right)}
Multiply -4 times -9.
a=\frac{-19±\sqrt{361-288}}{2\left(-9\right)}
Multiply 36 times -8.
a=\frac{-19±\sqrt{73}}{2\left(-9\right)}
Add 361 to -288.
a=\frac{-19±\sqrt{73}}{-18}
Multiply 2 times -9.
a=\frac{\sqrt{73}-19}{-18}
Now solve the equation a=\frac{-19±\sqrt{73}}{-18} when ± is plus. Add -19 to \sqrt{73}.
a=\frac{19-\sqrt{73}}{18}
Divide -19+\sqrt{73} by -18.
a=\frac{-\sqrt{73}-19}{-18}
Now solve the equation a=\frac{-19±\sqrt{73}}{-18} when ± is minus. Subtract \sqrt{73} from -19.
a=\frac{\sqrt{73}+19}{18}
Divide -19-\sqrt{73} by -18.
a=\frac{19-\sqrt{73}}{18} a=\frac{\sqrt{73}+19}{18}
The equation is now solved.
2\times 4+2a\left(-2\right)+a\left(2-a\right)\times \frac{2}{a-1}=3a
Variable a cannot be equal to 0 since division by zero is not defined. Multiply both sides of the equation by 2a, the least common multiple of a,2.
8+2a\left(-2\right)+a\left(2-a\right)\times \frac{2}{a-1}=3a
Multiply 2 and 4 to get 8.
8-4a+a\left(2-a\right)\times \frac{2}{a-1}=3a
Multiply 2 and -2 to get -4.
8-4a+\frac{a\times 2}{a-1}\left(2-a\right)=3a
Express a\times \frac{2}{a-1} as a single fraction.
8-4a+2\times \frac{a\times 2}{a-1}-\frac{a\times 2}{a-1}a=3a
Use the distributive property to multiply \frac{a\times 2}{a-1} by 2-a.
8-4a+\frac{2a\times 2}{a-1}-\frac{a\times 2}{a-1}a=3a
Express 2\times \frac{a\times 2}{a-1} as a single fraction.
8-4a+\frac{2a\times 2}{a-1}-\frac{a\times 2a}{a-1}=3a
Express \frac{a\times 2}{a-1}a as a single fraction.
8-4a+\frac{2a\times 2-a\times 2a}{a-1}=3a
Since \frac{2a\times 2}{a-1} and \frac{a\times 2a}{a-1} have the same denominator, subtract them by subtracting their numerators.
8-4a+\frac{4a-2a^{2}}{a-1}=3a
Do the multiplications in 2a\times 2-a\times 2a.
\frac{\left(8-4a\right)\left(a-1\right)}{a-1}+\frac{4a-2a^{2}}{a-1}=3a
To add or subtract expressions, expand them to make their denominators the same. Multiply 8-4a times \frac{a-1}{a-1}.
\frac{\left(8-4a\right)\left(a-1\right)+4a-2a^{2}}{a-1}=3a
Since \frac{\left(8-4a\right)\left(a-1\right)}{a-1} and \frac{4a-2a^{2}}{a-1} have the same denominator, add them by adding their numerators.
\frac{8a-8-4a^{2}+4a+4a-2a^{2}}{a-1}=3a
Do the multiplications in \left(8-4a\right)\left(a-1\right)+4a-2a^{2}.
\frac{16a-8-6a^{2}}{a-1}=3a
Combine like terms in 8a-8-4a^{2}+4a+4a-2a^{2}.
\frac{16a-8-6a^{2}}{a-1}-3a=0
Subtract 3a from both sides.
\frac{16a-8-6a^{2}}{a-1}+\frac{-3a\left(a-1\right)}{a-1}=0
To add or subtract expressions, expand them to make their denominators the same. Multiply -3a times \frac{a-1}{a-1}.
\frac{16a-8-6a^{2}-3a\left(a-1\right)}{a-1}=0
Since \frac{16a-8-6a^{2}}{a-1} and \frac{-3a\left(a-1\right)}{a-1} have the same denominator, add them by adding their numerators.
\frac{16a-8-6a^{2}-3a^{2}+3a}{a-1}=0
Do the multiplications in 16a-8-6a^{2}-3a\left(a-1\right).
\frac{19a-8-9a^{2}}{a-1}=0
Combine like terms in 16a-8-6a^{2}-3a^{2}+3a.
19a-8-9a^{2}=0
Variable a cannot be equal to 1 since division by zero is not defined. Multiply both sides of the equation by a-1.
19a-9a^{2}=8
Add 8 to both sides. Anything plus zero gives itself.
-9a^{2}+19a=8
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{-9a^{2}+19a}{-9}=\frac{8}{-9}
Divide both sides by -9.
a^{2}+\frac{19}{-9}a=\frac{8}{-9}
Dividing by -9 undoes the multiplication by -9.
a^{2}-\frac{19}{9}a=\frac{8}{-9}
Divide 19 by -9.
a^{2}-\frac{19}{9}a=-\frac{8}{9}
Divide 8 by -9.
a^{2}-\frac{19}{9}a+\left(-\frac{19}{18}\right)^{2}=-\frac{8}{9}+\left(-\frac{19}{18}\right)^{2}
Divide -\frac{19}{9}, the coefficient of the x term, by 2 to get -\frac{19}{18}. Then add the square of -\frac{19}{18} to both sides of the equation. This step makes the left hand side of the equation a perfect square.
a^{2}-\frac{19}{9}a+\frac{361}{324}=-\frac{8}{9}+\frac{361}{324}
Square -\frac{19}{18} by squaring both the numerator and the denominator of the fraction.
a^{2}-\frac{19}{9}a+\frac{361}{324}=\frac{73}{324}
Add -\frac{8}{9} to \frac{361}{324} by finding a common denominator and adding the numerators. Then reduce the fraction to lowest terms if possible.
\left(a-\frac{19}{18}\right)^{2}=\frac{73}{324}
Factor a^{2}-\frac{19}{9}a+\frac{361}{324}. 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(a-\frac{19}{18}\right)^{2}}=\sqrt{\frac{73}{324}}
Take the square root of both sides of the equation.
a-\frac{19}{18}=\frac{\sqrt{73}}{18} a-\frac{19}{18}=-\frac{\sqrt{73}}{18}
Simplify.
a=\frac{\sqrt{73}+19}{18} a=\frac{19-\sqrt{73}}{18}
Add \frac{19}{18} to 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}