Solve for k
k=-\frac{1}{6}\approx -0.166666667
k=0
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32\times \left(\frac{-k}{2}\right)^{2}+2\left(4\times \frac{-k}{2}-3\right)\left(-k\right)-4k=0
Multiply both sides of the equation by 2.
32\times \frac{\left(-k\right)^{2}}{2^{2}}+2\left(4\times \frac{-k}{2}-3\right)\left(-k\right)-4k=0
To raise \frac{-k}{2} to a power, raise both numerator and denominator to the power and then divide.
\frac{32\left(-k\right)^{2}}{2^{2}}+2\left(4\times \frac{-k}{2}-3\right)\left(-k\right)-4k=0
Express 32\times \frac{\left(-k\right)^{2}}{2^{2}} as a single fraction.
\frac{32\left(-k\right)^{2}}{2^{2}}+2\left(2\left(-k\right)-3\right)\left(-k\right)-4k=0
Cancel out 2, the greatest common factor in 4 and 2.
\frac{32\left(-k\right)^{2}}{2^{2}}+\left(4\left(-k\right)-6\right)\left(-k\right)-4k=0
Use the distributive property to multiply 2 by 2\left(-k\right)-3.
\frac{32\left(-k\right)^{2}}{2^{2}}+4\left(-k\right)^{2}-6\left(-k\right)-4k=0
Use the distributive property to multiply 4\left(-k\right)-6 by -k.
\frac{32\left(-k\right)^{2}}{2^{2}}+4k^{2}-6\left(-k\right)-4k=0
Calculate -k to the power of 2 and get k^{2}.
\frac{32\left(-k\right)^{2}}{2^{2}}+4k^{2}+6k-4k=0
Multiply -6 and -1 to get 6.
\frac{32\left(-k\right)^{2}}{2^{2}}+4k^{2}+2k=0
Combine 6k and -4k to get 2k.
\frac{32\left(-k\right)^{2}}{2^{2}}+\frac{\left(4k^{2}+2k\right)\times 2^{2}}{2^{2}}=0
To add or subtract expressions, expand them to make their denominators the same. Multiply 4k^{2}+2k times \frac{2^{2}}{2^{2}}.
\frac{32\left(-k\right)^{2}+\left(4k^{2}+2k\right)\times 2^{2}}{2^{2}}=0
Since \frac{32\left(-k\right)^{2}}{2^{2}} and \frac{\left(4k^{2}+2k\right)\times 2^{2}}{2^{2}} have the same denominator, add them by adding their numerators.
\frac{32\left(-k\right)^{2}}{2^{2}}+\frac{\left(4k^{2}+2k\right)\times 2^{2}}{2^{2}}=0
To add or subtract expressions, expand them to make their denominators the same. Multiply 4k^{2}+2k times \frac{2^{2}}{2^{2}}.
\frac{32\left(-k\right)^{2}+\left(4k^{2}+2k\right)\times 2^{2}}{2^{2}}=0
Since \frac{32\left(-k\right)^{2}}{2^{2}} and \frac{\left(4k^{2}+2k\right)\times 2^{2}}{2^{2}} have the same denominator, add them by adding their numerators.
\frac{32k^{2}+\left(4k^{2}+2k\right)\times 2^{2}}{2^{2}}=0
Calculate -k to the power of 2 and get k^{2}.
\frac{32k^{2}+\left(4k^{2}+2k\right)\times 4}{2^{2}}=0
Calculate 2 to the power of 2 and get 4.
\frac{32k^{2}+\left(4k^{2}+2k\right)\times 4}{4}=0
Calculate 2 to the power of 2 and get 4.
8k^{2}+4k^{2}+2k=0
Divide each term of 32k^{2}+\left(4k^{2}+2k\right)\times 4 by 4 to get 8k^{2}+4k^{2}+2k.
12k^{2}+2k=0
Combine 8k^{2} and 4k^{2} to get 12k^{2}.
k\left(12k+2\right)=0
Factor out k.
k=0 k=-\frac{1}{6}
To find equation solutions, solve k=0 and 12k+2=0.
32\times \left(\frac{-k}{2}\right)^{2}+2\left(4\times \frac{-k}{2}-3\right)\left(-k\right)-4k=0
Multiply both sides of the equation by 2.
32\times \frac{\left(-k\right)^{2}}{2^{2}}+2\left(4\times \frac{-k}{2}-3\right)\left(-k\right)-4k=0
To raise \frac{-k}{2} to a power, raise both numerator and denominator to the power and then divide.
\frac{32\left(-k\right)^{2}}{2^{2}}+2\left(4\times \frac{-k}{2}-3\right)\left(-k\right)-4k=0
Express 32\times \frac{\left(-k\right)^{2}}{2^{2}} as a single fraction.
\frac{32\left(-k\right)^{2}}{2^{2}}+2\left(2\left(-k\right)-3\right)\left(-k\right)-4k=0
Cancel out 2, the greatest common factor in 4 and 2.
\frac{32\left(-k\right)^{2}}{2^{2}}+\left(4\left(-k\right)-6\right)\left(-k\right)-4k=0
Use the distributive property to multiply 2 by 2\left(-k\right)-3.
\frac{32\left(-k\right)^{2}}{2^{2}}+4\left(-k\right)^{2}-6\left(-k\right)-4k=0
Use the distributive property to multiply 4\left(-k\right)-6 by -k.
\frac{32\left(-k\right)^{2}}{2^{2}}+4k^{2}-6\left(-k\right)-4k=0
Calculate -k to the power of 2 and get k^{2}.
\frac{32\left(-k\right)^{2}}{2^{2}}+4k^{2}+6k-4k=0
Multiply -6 and -1 to get 6.
\frac{32\left(-k\right)^{2}}{2^{2}}+4k^{2}+2k=0
Combine 6k and -4k to get 2k.
\frac{32\left(-k\right)^{2}}{2^{2}}+\frac{\left(4k^{2}+2k\right)\times 2^{2}}{2^{2}}=0
To add or subtract expressions, expand them to make their denominators the same. Multiply 4k^{2}+2k times \frac{2^{2}}{2^{2}}.
\frac{32\left(-k\right)^{2}+\left(4k^{2}+2k\right)\times 2^{2}}{2^{2}}=0
Since \frac{32\left(-k\right)^{2}}{2^{2}} and \frac{\left(4k^{2}+2k\right)\times 2^{2}}{2^{2}} have the same denominator, add them by adding their numerators.
\frac{32k^{2}+\left(4k^{2}+2k\right)\times 2^{2}}{2^{2}}=0
Calculate -k to the power of 2 and get k^{2}.
\frac{32k^{2}+\left(4k^{2}+2k\right)\times 4}{2^{2}}=0
Calculate 2 to the power of 2 and get 4.
\frac{32k^{2}+\left(4k^{2}+2k\right)\times 4}{4}=0
Calculate 2 to the power of 2 and get 4.
8k^{2}+4k^{2}+2k=0
Divide each term of 32k^{2}+\left(4k^{2}+2k\right)\times 4 by 4 to get 8k^{2}+4k^{2}+2k.
12k^{2}+2k=0
Combine 8k^{2} and 4k^{2} to get 12k^{2}.
k=\frac{-2±\sqrt{2^{2}}}{2\times 12}
This equation is in standard form: ax^{2}+bx+c=0. Substitute 12 for a, 2 for b, and 0 for c in the quadratic formula, \frac{-b±\sqrt{b^{2}-4ac}}{2a}.
k=\frac{-2±2}{2\times 12}
Take the square root of 2^{2}.
k=\frac{-2±2}{24}
Multiply 2 times 12.
k=\frac{0}{24}
Now solve the equation k=\frac{-2±2}{24} when ± is plus. Add -2 to 2.
k=0
Divide 0 by 24.
k=-\frac{4}{24}
Now solve the equation k=\frac{-2±2}{24} when ± is minus. Subtract 2 from -2.
k=-\frac{1}{6}
Reduce the fraction \frac{-4}{24} to lowest terms by extracting and canceling out 4.
k=0 k=-\frac{1}{6}
The equation is now solved.
32\times \left(\frac{-k}{2}\right)^{2}+2\left(4\times \frac{-k}{2}-3\right)\left(-k\right)-4k=0
Multiply both sides of the equation by 2.
32\times \frac{\left(-k\right)^{2}}{2^{2}}+2\left(4\times \frac{-k}{2}-3\right)\left(-k\right)-4k=0
To raise \frac{-k}{2} to a power, raise both numerator and denominator to the power and then divide.
\frac{32\left(-k\right)^{2}}{2^{2}}+2\left(4\times \frac{-k}{2}-3\right)\left(-k\right)-4k=0
Express 32\times \frac{\left(-k\right)^{2}}{2^{2}} as a single fraction.
\frac{32\left(-k\right)^{2}}{2^{2}}+2\left(2\left(-k\right)-3\right)\left(-k\right)-4k=0
Cancel out 2, the greatest common factor in 4 and 2.
\frac{32\left(-k\right)^{2}}{2^{2}}+\left(4\left(-k\right)-6\right)\left(-k\right)-4k=0
Use the distributive property to multiply 2 by 2\left(-k\right)-3.
\frac{32\left(-k\right)^{2}}{2^{2}}+4\left(-k\right)^{2}-6\left(-k\right)-4k=0
Use the distributive property to multiply 4\left(-k\right)-6 by -k.
\frac{32\left(-k\right)^{2}}{2^{2}}+4k^{2}-6\left(-k\right)-4k=0
Calculate -k to the power of 2 and get k^{2}.
\frac{32\left(-k\right)^{2}}{2^{2}}+4k^{2}+6k-4k=0
Multiply -6 and -1 to get 6.
\frac{32\left(-k\right)^{2}}{2^{2}}+4k^{2}+2k=0
Combine 6k and -4k to get 2k.
\frac{32\left(-k\right)^{2}}{2^{2}}+\frac{\left(4k^{2}+2k\right)\times 2^{2}}{2^{2}}=0
To add or subtract expressions, expand them to make their denominators the same. Multiply 4k^{2}+2k times \frac{2^{2}}{2^{2}}.
\frac{32\left(-k\right)^{2}+\left(4k^{2}+2k\right)\times 2^{2}}{2^{2}}=0
Since \frac{32\left(-k\right)^{2}}{2^{2}} and \frac{\left(4k^{2}+2k\right)\times 2^{2}}{2^{2}} have the same denominator, add them by adding their numerators.
\frac{32k^{2}+\left(4k^{2}+2k\right)\times 2^{2}}{2^{2}}=0
Calculate -k to the power of 2 and get k^{2}.
\frac{32k^{2}+\left(4k^{2}+2k\right)\times 4}{2^{2}}=0
Calculate 2 to the power of 2 and get 4.
\frac{32k^{2}+\left(4k^{2}+2k\right)\times 4}{4}=0
Calculate 2 to the power of 2 and get 4.
8k^{2}+4k^{2}+2k=0
Divide each term of 32k^{2}+\left(4k^{2}+2k\right)\times 4 by 4 to get 8k^{2}+4k^{2}+2k.
12k^{2}+2k=0
Combine 8k^{2} and 4k^{2} to get 12k^{2}.
\frac{12k^{2}+2k}{12}=\frac{0}{12}
Divide both sides by 12.
k^{2}+\frac{2}{12}k=\frac{0}{12}
Dividing by 12 undoes the multiplication by 12.
k^{2}+\frac{1}{6}k=\frac{0}{12}
Reduce the fraction \frac{2}{12} to lowest terms by extracting and canceling out 2.
k^{2}+\frac{1}{6}k=0
Divide 0 by 12.
k^{2}+\frac{1}{6}k+\left(\frac{1}{12}\right)^{2}=\left(\frac{1}{12}\right)^{2}
Divide \frac{1}{6}, the coefficient of the x term, by 2 to get \frac{1}{12}. Then add the square of \frac{1}{12} to both sides of the equation. This step makes the left hand side of the equation a perfect square.
k^{2}+\frac{1}{6}k+\frac{1}{144}=\frac{1}{144}
Square \frac{1}{12} by squaring both the numerator and the denominator of the fraction.
\left(k+\frac{1}{12}\right)^{2}=\frac{1}{144}
Factor k^{2}+\frac{1}{6}k+\frac{1}{144}. 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(k+\frac{1}{12}\right)^{2}}=\sqrt{\frac{1}{144}}
Take the square root of both sides of the equation.
k+\frac{1}{12}=\frac{1}{12} k+\frac{1}{12}=-\frac{1}{12}
Simplify.
k=0 k=-\frac{1}{6}
Subtract \frac{1}{12} from both sides of the equation.
Examples
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{ x } ^ { 2 } - 4 x - 5 = 0
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4 \sin \theta \cos \theta = 2 \sin \theta
Linear equation
y = 3x + 4
Arithmetic
699 * 533
Matrix
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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}