Solve for t
t=2
t=4
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t\left(6-t\right)=8
Cancel out 2 and 2.
6t-t^{2}=8
Use the distributive property to multiply t by 6-t.
6t-t^{2}-8=0
Subtract 8 from both sides.
-t^{2}+6t-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{-6±\sqrt{6^{2}-4\left(-1\right)\left(-8\right)}}{2\left(-1\right)}
This equation is in standard form: ax^{2}+bx+c=0. Substitute -1 for a, 6 for b, and -8 for c in the quadratic formula, \frac{-b±\sqrt{b^{2}-4ac}}{2a}.
t=\frac{-6±\sqrt{36-4\left(-1\right)\left(-8\right)}}{2\left(-1\right)}
Square 6.
t=\frac{-6±\sqrt{36+4\left(-8\right)}}{2\left(-1\right)}
Multiply -4 times -1.
t=\frac{-6±\sqrt{36-32}}{2\left(-1\right)}
Multiply 4 times -8.
t=\frac{-6±\sqrt{4}}{2\left(-1\right)}
Add 36 to -32.
t=\frac{-6±2}{2\left(-1\right)}
Take the square root of 4.
t=\frac{-6±2}{-2}
Multiply 2 times -1.
t=-\frac{4}{-2}
Now solve the equation t=\frac{-6±2}{-2} when ± is plus. Add -6 to 2.
t=2
Divide -4 by -2.
t=-\frac{8}{-2}
Now solve the equation t=\frac{-6±2}{-2} when ± is minus. Subtract 2 from -6.
t=4
Divide -8 by -2.
t=2 t=4
The equation is now solved.
t\left(6-t\right)=8
Cancel out 2 and 2.
6t-t^{2}=8
Use the distributive property to multiply t by 6-t.
-t^{2}+6t=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{-t^{2}+6t}{-1}=\frac{8}{-1}
Divide both sides by -1.
t^{2}+\frac{6}{-1}t=\frac{8}{-1}
Dividing by -1 undoes the multiplication by -1.
t^{2}-6t=\frac{8}{-1}
Divide 6 by -1.
t^{2}-6t=-8
Divide 8 by -1.
t^{2}-6t+\left(-3\right)^{2}=-8+\left(-3\right)^{2}
Divide -6, the coefficient of the x term, by 2 to get -3. Then add the square of -3 to both sides of the equation. This step makes the left hand side of the equation a perfect square.
t^{2}-6t+9=-8+9
Square -3.
t^{2}-6t+9=1
Add -8 to 9.
\left(t-3\right)^{2}=1
Factor t^{2}-6t+9. 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-3\right)^{2}}=\sqrt{1}
Take the square root of both sides of the equation.
t-3=1 t-3=-1
Simplify.
t=4 t=2
Add 3 to both sides of the equation.
Examples
Quadratic equation
{ 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}