Solve for a
a=\sqrt{29}+2\approx 7.385164807
a=2-\sqrt{29}\approx -3.385164807
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\left(a+1\right)a-a\left(a+1\right)+25=\left(a+1\right)a+\left(a+1\right)\left(-1\right)-\left(4a-1\right)
Variable a cannot be equal to -1 since division by zero is not defined. Multiply both sides of the equation by a+1.
a^{2}+a-a\left(a+1\right)+25=\left(a+1\right)a+\left(a+1\right)\left(-1\right)-\left(4a-1\right)
Use the distributive property to multiply a+1 by a.
a^{2}+a-a^{2}-a+25=\left(a+1\right)a+\left(a+1\right)\left(-1\right)-\left(4a-1\right)
Use the distributive property to multiply -a by a+1.
a-a+25=\left(a+1\right)a+\left(a+1\right)\left(-1\right)-\left(4a-1\right)
Combine a^{2} and -a^{2} to get 0.
25=\left(a+1\right)a+\left(a+1\right)\left(-1\right)-\left(4a-1\right)
Combine a and -a to get 0.
25=a^{2}+a+\left(a+1\right)\left(-1\right)-\left(4a-1\right)
Use the distributive property to multiply a+1 by a.
25=a^{2}+a-a-1-\left(4a-1\right)
Use the distributive property to multiply a+1 by -1.
25=a^{2}-1-\left(4a-1\right)
Combine a and -a to get 0.
25=a^{2}-1-4a+1
To find the opposite of 4a-1, find the opposite of each term.
25=a^{2}-4a
Add -1 and 1 to get 0.
a^{2}-4a=25
Swap sides so that all variable terms are on the left hand side.
a^{2}-4a-25=0
Subtract 25 from both sides.
a=\frac{-\left(-4\right)±\sqrt{\left(-4\right)^{2}-4\left(-25\right)}}{2}
This equation is in standard form: ax^{2}+bx+c=0. Substitute 1 for a, -4 for b, and -25 for c in the quadratic formula, \frac{-b±\sqrt{b^{2}-4ac}}{2a}.
a=\frac{-\left(-4\right)±\sqrt{16-4\left(-25\right)}}{2}
Square -4.
a=\frac{-\left(-4\right)±\sqrt{16+100}}{2}
Multiply -4 times -25.
a=\frac{-\left(-4\right)±\sqrt{116}}{2}
Add 16 to 100.
a=\frac{-\left(-4\right)±2\sqrt{29}}{2}
Take the square root of 116.
a=\frac{4±2\sqrt{29}}{2}
The opposite of -4 is 4.
a=\frac{2\sqrt{29}+4}{2}
Now solve the equation a=\frac{4±2\sqrt{29}}{2} when ± is plus. Add 4 to 2\sqrt{29}.
a=\sqrt{29}+2
Divide 4+2\sqrt{29} by 2.
a=\frac{4-2\sqrt{29}}{2}
Now solve the equation a=\frac{4±2\sqrt{29}}{2} when ± is minus. Subtract 2\sqrt{29} from 4.
a=2-\sqrt{29}
Divide 4-2\sqrt{29} by 2.
a=\sqrt{29}+2 a=2-\sqrt{29}
The equation is now solved.
\left(a+1\right)a-a\left(a+1\right)+25=\left(a+1\right)a+\left(a+1\right)\left(-1\right)-\left(4a-1\right)
Variable a cannot be equal to -1 since division by zero is not defined. Multiply both sides of the equation by a+1.
a^{2}+a-a\left(a+1\right)+25=\left(a+1\right)a+\left(a+1\right)\left(-1\right)-\left(4a-1\right)
Use the distributive property to multiply a+1 by a.
a^{2}+a-a^{2}-a+25=\left(a+1\right)a+\left(a+1\right)\left(-1\right)-\left(4a-1\right)
Use the distributive property to multiply -a by a+1.
a-a+25=\left(a+1\right)a+\left(a+1\right)\left(-1\right)-\left(4a-1\right)
Combine a^{2} and -a^{2} to get 0.
25=\left(a+1\right)a+\left(a+1\right)\left(-1\right)-\left(4a-1\right)
Combine a and -a to get 0.
25=a^{2}+a+\left(a+1\right)\left(-1\right)-\left(4a-1\right)
Use the distributive property to multiply a+1 by a.
25=a^{2}+a-a-1-\left(4a-1\right)
Use the distributive property to multiply a+1 by -1.
25=a^{2}-1-\left(4a-1\right)
Combine a and -a to get 0.
25=a^{2}-1-4a+1
To find the opposite of 4a-1, find the opposite of each term.
25=a^{2}-4a
Add -1 and 1 to get 0.
a^{2}-4a=25
Swap sides so that all variable terms are on the left hand side.
a^{2}-4a+\left(-2\right)^{2}=25+\left(-2\right)^{2}
Divide -4, the coefficient of the x term, by 2 to get -2. Then add the square of -2 to both sides of the equation. This step makes the left hand side of the equation a perfect square.
a^{2}-4a+4=25+4
Square -2.
a^{2}-4a+4=29
Add 25 to 4.
\left(a-2\right)^{2}=29
Factor a^{2}-4a+4. 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-2\right)^{2}}=\sqrt{29}
Take the square root of both sides of the equation.
a-2=\sqrt{29} a-2=-\sqrt{29}
Simplify.
a=\sqrt{29}+2 a=2-\sqrt{29}
Add 2 to both sides of the equation.
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Simultaneous equation
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Differentiation
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Integration
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Limits
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