Solve for a
a=-1
a=3
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10=\frac{\left(a-5\right)^{2}}{2^{2}}+a^{2}
To raise \frac{a-5}{2} to a power, raise both numerator and denominator to the power and then divide.
10=\frac{\left(a-5\right)^{2}}{2^{2}}+\frac{a^{2}\times 2^{2}}{2^{2}}
To add or subtract expressions, expand them to make their denominators the same. Multiply a^{2} times \frac{2^{2}}{2^{2}}.
10=\frac{\left(a-5\right)^{2}+a^{2}\times 2^{2}}{2^{2}}
Since \frac{\left(a-5\right)^{2}}{2^{2}} and \frac{a^{2}\times 2^{2}}{2^{2}} have the same denominator, add them by adding their numerators.
10=\frac{a^{2}-10a+25+4a^{2}}{2^{2}}
Do the multiplications in \left(a-5\right)^{2}+a^{2}\times 2^{2}.
10=\frac{5a^{2}-10a+25}{2^{2}}
Combine like terms in a^{2}-10a+25+4a^{2}.
10=\frac{5a^{2}-10a+25}{4}
Calculate 2 to the power of 2 and get 4.
10=\frac{5}{4}a^{2}-\frac{5}{2}a+\frac{25}{4}
Divide each term of 5a^{2}-10a+25 by 4 to get \frac{5}{4}a^{2}-\frac{5}{2}a+\frac{25}{4}.
\frac{5}{4}a^{2}-\frac{5}{2}a+\frac{25}{4}=10
Swap sides so that all variable terms are on the left hand side.
\frac{5}{4}a^{2}-\frac{5}{2}a+\frac{25}{4}-10=0
Subtract 10 from both sides.
\frac{5}{4}a^{2}-\frac{5}{2}a-\frac{15}{4}=0
Subtract 10 from \frac{25}{4} to get -\frac{15}{4}.
a=\frac{-\left(-\frac{5}{2}\right)±\sqrt{\left(-\frac{5}{2}\right)^{2}-4\times \frac{5}{4}\left(-\frac{15}{4}\right)}}{2\times \frac{5}{4}}
This equation is in standard form: ax^{2}+bx+c=0. Substitute \frac{5}{4} for a, -\frac{5}{2} for b, and -\frac{15}{4} for c in the quadratic formula, \frac{-b±\sqrt{b^{2}-4ac}}{2a}.
a=\frac{-\left(-\frac{5}{2}\right)±\sqrt{\frac{25}{4}-4\times \frac{5}{4}\left(-\frac{15}{4}\right)}}{2\times \frac{5}{4}}
Square -\frac{5}{2} by squaring both the numerator and the denominator of the fraction.
a=\frac{-\left(-\frac{5}{2}\right)±\sqrt{\frac{25}{4}-5\left(-\frac{15}{4}\right)}}{2\times \frac{5}{4}}
Multiply -4 times \frac{5}{4}.
a=\frac{-\left(-\frac{5}{2}\right)±\sqrt{\frac{25+75}{4}}}{2\times \frac{5}{4}}
Multiply -5 times -\frac{15}{4}.
a=\frac{-\left(-\frac{5}{2}\right)±\sqrt{25}}{2\times \frac{5}{4}}
Add \frac{25}{4} to \frac{75}{4} by finding a common denominator and adding the numerators. Then reduce the fraction to lowest terms if possible.
a=\frac{-\left(-\frac{5}{2}\right)±5}{2\times \frac{5}{4}}
Take the square root of 25.
a=\frac{\frac{5}{2}±5}{2\times \frac{5}{4}}
The opposite of -\frac{5}{2} is \frac{5}{2}.
a=\frac{\frac{5}{2}±5}{\frac{5}{2}}
Multiply 2 times \frac{5}{4}.
a=\frac{\frac{15}{2}}{\frac{5}{2}}
Now solve the equation a=\frac{\frac{5}{2}±5}{\frac{5}{2}} when ± is plus. Add \frac{5}{2} to 5.
a=3
Divide \frac{15}{2} by \frac{5}{2} by multiplying \frac{15}{2} by the reciprocal of \frac{5}{2}.
a=-\frac{\frac{5}{2}}{\frac{5}{2}}
Now solve the equation a=\frac{\frac{5}{2}±5}{\frac{5}{2}} when ± is minus. Subtract 5 from \frac{5}{2}.
a=-1
Divide -\frac{5}{2} by \frac{5}{2} by multiplying -\frac{5}{2} by the reciprocal of \frac{5}{2}.
a=3 a=-1
The equation is now solved.
10=\frac{\left(a-5\right)^{2}}{2^{2}}+a^{2}
To raise \frac{a-5}{2} to a power, raise both numerator and denominator to the power and then divide.
10=\frac{\left(a-5\right)^{2}}{2^{2}}+\frac{a^{2}\times 2^{2}}{2^{2}}
To add or subtract expressions, expand them to make their denominators the same. Multiply a^{2} times \frac{2^{2}}{2^{2}}.
10=\frac{\left(a-5\right)^{2}+a^{2}\times 2^{2}}{2^{2}}
Since \frac{\left(a-5\right)^{2}}{2^{2}} and \frac{a^{2}\times 2^{2}}{2^{2}} have the same denominator, add them by adding their numerators.
10=\frac{a^{2}-10a+25+4a^{2}}{2^{2}}
Do the multiplications in \left(a-5\right)^{2}+a^{2}\times 2^{2}.
10=\frac{5a^{2}-10a+25}{2^{2}}
Combine like terms in a^{2}-10a+25+4a^{2}.
10=\frac{5a^{2}-10a+25}{4}
Calculate 2 to the power of 2 and get 4.
10=\frac{5}{4}a^{2}-\frac{5}{2}a+\frac{25}{4}
Divide each term of 5a^{2}-10a+25 by 4 to get \frac{5}{4}a^{2}-\frac{5}{2}a+\frac{25}{4}.
\frac{5}{4}a^{2}-\frac{5}{2}a+\frac{25}{4}=10
Swap sides so that all variable terms are on the left hand side.
\frac{5}{4}a^{2}-\frac{5}{2}a=10-\frac{25}{4}
Subtract \frac{25}{4} from both sides.
\frac{5}{4}a^{2}-\frac{5}{2}a=\frac{15}{4}
Subtract \frac{25}{4} from 10 to get \frac{15}{4}.
\frac{\frac{5}{4}a^{2}-\frac{5}{2}a}{\frac{5}{4}}=\frac{\frac{15}{4}}{\frac{5}{4}}
Divide both sides of the equation by \frac{5}{4}, which is the same as multiplying both sides by the reciprocal of the fraction.
a^{2}+\left(-\frac{\frac{5}{2}}{\frac{5}{4}}\right)a=\frac{\frac{15}{4}}{\frac{5}{4}}
Dividing by \frac{5}{4} undoes the multiplication by \frac{5}{4}.
a^{2}-2a=\frac{\frac{15}{4}}{\frac{5}{4}}
Divide -\frac{5}{2} by \frac{5}{4} by multiplying -\frac{5}{2} by the reciprocal of \frac{5}{4}.
a^{2}-2a=3
Divide \frac{15}{4} by \frac{5}{4} by multiplying \frac{15}{4} by the reciprocal of \frac{5}{4}.
a^{2}-2a+1=3+1
Divide -2, the coefficient of the x term, by 2 to get -1. Then add the square of -1 to both sides of the equation. This step makes the left hand side of the equation a perfect square.
a^{2}-2a+1=4
Add 3 to 1.
\left(a-1\right)^{2}=4
Factor a^{2}-2a+1. 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-1\right)^{2}}=\sqrt{4}
Take the square root of both sides of the equation.
a-1=2 a-1=-2
Simplify.
a=3 a=-1
Add 1 to both sides of the equation.
Examples
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{ 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}