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2\left(4-2t\right)=t\times 2t
Variable t cannot be equal to 0 since division by zero is not defined. Multiply both sides of the equation by 4t, the least common multiple of 2t,4.
8-4t=t\times 2t
Use the distributive property to multiply 2 by 4-2t.
8-4t=t^{2}\times 2
Multiply t and t to get t^{2}.
8-4t-t^{2}\times 2=0
Subtract t^{2}\times 2 from both sides.
8-4t-2t^{2}=0
Multiply -1 and 2 to get -2.
-2t^{2}-4t+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.
t=\frac{-\left(-4\right)±\sqrt{\left(-4\right)^{2}-4\left(-2\right)\times 8}}{2\left(-2\right)}
This equation is in standard form: ax^{2}+bx+c=0. Substitute -2 for a, -4 for b, and 8 for c in the quadratic formula, \frac{-b±\sqrt{b^{2}-4ac}}{2a}.
t=\frac{-\left(-4\right)±\sqrt{16-4\left(-2\right)\times 8}}{2\left(-2\right)}
Square -4.
t=\frac{-\left(-4\right)±\sqrt{16+8\times 8}}{2\left(-2\right)}
Multiply -4 times -2.
t=\frac{-\left(-4\right)±\sqrt{16+64}}{2\left(-2\right)}
Multiply 8 times 8.
t=\frac{-\left(-4\right)±\sqrt{80}}{2\left(-2\right)}
Add 16 to 64.
t=\frac{-\left(-4\right)±4\sqrt{5}}{2\left(-2\right)}
Take the square root of 80.
t=\frac{4±4\sqrt{5}}{2\left(-2\right)}
The opposite of -4 is 4.
t=\frac{4±4\sqrt{5}}{-4}
Multiply 2 times -2.
t=\frac{4\sqrt{5}+4}{-4}
Now solve the equation t=\frac{4±4\sqrt{5}}{-4} when ± is plus. Add 4 to 4\sqrt{5}.
t=-\left(\sqrt{5}+1\right)
Divide 4+4\sqrt{5} by -4.
t=\frac{4-4\sqrt{5}}{-4}
Now solve the equation t=\frac{4±4\sqrt{5}}{-4} when ± is minus. Subtract 4\sqrt{5} from 4.
t=\sqrt{5}-1
Divide 4-4\sqrt{5} by -4.
t=-\left(\sqrt{5}+1\right) t=\sqrt{5}-1
The equation is now solved.
2\left(4-2t\right)=t\times 2t
Variable t cannot be equal to 0 since division by zero is not defined. Multiply both sides of the equation by 4t, the least common multiple of 2t,4.
8-4t=t\times 2t
Use the distributive property to multiply 2 by 4-2t.
8-4t=t^{2}\times 2
Multiply t and t to get t^{2}.
8-4t-t^{2}\times 2=0
Subtract t^{2}\times 2 from both sides.
8-4t-2t^{2}=0
Multiply -1 and 2 to get -2.
-4t-2t^{2}=-8
Subtract 8 from both sides. Anything subtracted from zero gives its negation.
-2t^{2}-4t=-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{-2t^{2}-4t}{-2}=-\frac{8}{-2}
Divide both sides by -2.
t^{2}+\left(-\frac{4}{-2}\right)t=-\frac{8}{-2}
Dividing by -2 undoes the multiplication by -2.
t^{2}+2t=-\frac{8}{-2}
Divide -4 by -2.
t^{2}+2t=4
Divide -8 by -2.
t^{2}+2t+1^{2}=4+1^{2}
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.
t^{2}+2t+1=4+1
Square 1.
t^{2}+2t+1=5
Add 4 to 1.
\left(t+1\right)^{2}=5
Factor t^{2}+2t+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(t+1\right)^{2}}=\sqrt{5}
Take the square root of both sides of the equation.
t+1=\sqrt{5} t+1=-\sqrt{5}
Simplify.
t=\sqrt{5}-1 t=-\sqrt{5}-1
Subtract 1 from both sides of the equation.