Solve for k
k=\sqrt{73}\approx 8.544003745
k=-\sqrt{73}\approx -8.544003745
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2k^{2}=144+2
Add 2 to both sides.
2k^{2}=146
Add 144 and 2 to get 146.
k^{2}=\frac{146}{2}
Divide both sides by 2.
k^{2}=73
Divide 146 by 2 to get 73.
k=\sqrt{73} k=-\sqrt{73}
Take the square root of both sides of the equation.
2k^{2}-2-144=0
Subtract 144 from both sides.
2k^{2}-146=0
Subtract 144 from -2 to get -146.
k=\frac{0±\sqrt{0^{2}-4\times 2\left(-146\right)}}{2\times 2}
This equation is in standard form: ax^{2}+bx+c=0. Substitute 2 for a, 0 for b, and -146 for c in the quadratic formula, \frac{-b±\sqrt{b^{2}-4ac}}{2a}.
k=\frac{0±\sqrt{-4\times 2\left(-146\right)}}{2\times 2}
Square 0.
k=\frac{0±\sqrt{-8\left(-146\right)}}{2\times 2}
Multiply -4 times 2.
k=\frac{0±\sqrt{1168}}{2\times 2}
Multiply -8 times -146.
k=\frac{0±4\sqrt{73}}{2\times 2}
Take the square root of 1168.
k=\frac{0±4\sqrt{73}}{4}
Multiply 2 times 2.
k=\sqrt{73}
Now solve the equation k=\frac{0±4\sqrt{73}}{4} when ± is plus.
k=-\sqrt{73}
Now solve the equation k=\frac{0±4\sqrt{73}}{4} when ± is minus.
k=\sqrt{73} k=-\sqrt{73}
The equation is now solved.
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