Solve for t
t=-5
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\left(t+2\right)t+t-2=8
Variable t cannot be equal to any of the values -2,2 since division by zero is not defined. Multiply both sides of the equation by \left(t-2\right)\left(t+2\right), the least common multiple of t-2,t+2,t^{2}-4.
t^{2}+2t+t-2=8
Use the distributive property to multiply t+2 by t.
t^{2}+3t-2=8
Combine 2t and t to get 3t.
t^{2}+3t-2-8=0
Subtract 8 from both sides.
t^{2}+3t-10=0
Subtract 8 from -2 to get -10.
a+b=3 ab=-10
To solve the equation, factor t^{2}+3t-10 using formula t^{2}+\left(a+b\right)t+ab=\left(t+a\right)\left(t+b\right). To find a and b, set up a system to be solved.
-1,10 -2,5
Since ab is negative, a and b have the opposite signs. Since a+b is positive, the positive number has greater absolute value than the negative. List all such integer pairs that give product -10.
-1+10=9 -2+5=3
Calculate the sum for each pair.
a=-2 b=5
The solution is the pair that gives sum 3.
\left(t-2\right)\left(t+5\right)
Rewrite factored expression \left(t+a\right)\left(t+b\right) using the obtained values.
t=2 t=-5
To find equation solutions, solve t-2=0 and t+5=0.
t=-5
Variable t cannot be equal to 2.
\left(t+2\right)t+t-2=8
Variable t cannot be equal to any of the values -2,2 since division by zero is not defined. Multiply both sides of the equation by \left(t-2\right)\left(t+2\right), the least common multiple of t-2,t+2,t^{2}-4.
t^{2}+2t+t-2=8
Use the distributive property to multiply t+2 by t.
t^{2}+3t-2=8
Combine 2t and t to get 3t.
t^{2}+3t-2-8=0
Subtract 8 from both sides.
t^{2}+3t-10=0
Subtract 8 from -2 to get -10.
a+b=3 ab=1\left(-10\right)=-10
To solve the equation, factor the left hand side by grouping. First, left hand side needs to be rewritten as t^{2}+at+bt-10. To find a and b, set up a system to be solved.
-1,10 -2,5
Since ab is negative, a and b have the opposite signs. Since a+b is positive, the positive number has greater absolute value than the negative. List all such integer pairs that give product -10.
-1+10=9 -2+5=3
Calculate the sum for each pair.
a=-2 b=5
The solution is the pair that gives sum 3.
\left(t^{2}-2t\right)+\left(5t-10\right)
Rewrite t^{2}+3t-10 as \left(t^{2}-2t\right)+\left(5t-10\right).
t\left(t-2\right)+5\left(t-2\right)
Factor out t in the first and 5 in the second group.
\left(t-2\right)\left(t+5\right)
Factor out common term t-2 by using distributive property.
t=2 t=-5
To find equation solutions, solve t-2=0 and t+5=0.
t=-5
Variable t cannot be equal to 2.
\left(t+2\right)t+t-2=8
Variable t cannot be equal to any of the values -2,2 since division by zero is not defined. Multiply both sides of the equation by \left(t-2\right)\left(t+2\right), the least common multiple of t-2,t+2,t^{2}-4.
t^{2}+2t+t-2=8
Use the distributive property to multiply t+2 by t.
t^{2}+3t-2=8
Combine 2t and t to get 3t.
t^{2}+3t-2-8=0
Subtract 8 from both sides.
t^{2}+3t-10=0
Subtract 8 from -2 to get -10.
t=\frac{-3±\sqrt{3^{2}-4\left(-10\right)}}{2}
This equation is in standard form: ax^{2}+bx+c=0. Substitute 1 for a, 3 for b, and -10 for c in the quadratic formula, \frac{-b±\sqrt{b^{2}-4ac}}{2a}.
t=\frac{-3±\sqrt{9-4\left(-10\right)}}{2}
Square 3.
t=\frac{-3±\sqrt{9+40}}{2}
Multiply -4 times -10.
t=\frac{-3±\sqrt{49}}{2}
Add 9 to 40.
t=\frac{-3±7}{2}
Take the square root of 49.
t=\frac{4}{2}
Now solve the equation t=\frac{-3±7}{2} when ± is plus. Add -3 to 7.
t=2
Divide 4 by 2.
t=-\frac{10}{2}
Now solve the equation t=\frac{-3±7}{2} when ± is minus. Subtract 7 from -3.
t=-5
Divide -10 by 2.
t=2 t=-5
The equation is now solved.
t=-5
Variable t cannot be equal to 2.
\left(t+2\right)t+t-2=8
Variable t cannot be equal to any of the values -2,2 since division by zero is not defined. Multiply both sides of the equation by \left(t-2\right)\left(t+2\right), the least common multiple of t-2,t+2,t^{2}-4.
t^{2}+2t+t-2=8
Use the distributive property to multiply t+2 by t.
t^{2}+3t-2=8
Combine 2t and t to get 3t.
t^{2}+3t=8+2
Add 2 to both sides.
t^{2}+3t=10
Add 8 and 2 to get 10.
t^{2}+3t+\left(\frac{3}{2}\right)^{2}=10+\left(\frac{3}{2}\right)^{2}
Divide 3, the coefficient of the x term, by 2 to get \frac{3}{2}. Then add the square of \frac{3}{2} to both sides of the equation. This step makes the left hand side of the equation a perfect square.
t^{2}+3t+\frac{9}{4}=10+\frac{9}{4}
Square \frac{3}{2} by squaring both the numerator and the denominator of the fraction.
t^{2}+3t+\frac{9}{4}=\frac{49}{4}
Add 10 to \frac{9}{4}.
\left(t+\frac{3}{2}\right)^{2}=\frac{49}{4}
Factor t^{2}+3t+\frac{9}{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(t+\frac{3}{2}\right)^{2}}=\sqrt{\frac{49}{4}}
Take the square root of both sides of the equation.
t+\frac{3}{2}=\frac{7}{2} t+\frac{3}{2}=-\frac{7}{2}
Simplify.
t=2 t=-5
Subtract \frac{3}{2} from both sides of the equation.
t=-5
Variable t cannot be equal to 2.
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