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6t^2-5t-4=0 equation

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Numerical solution:

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The solution

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6*t  - 5*t - 4 = 0
$$\left(6 t^{2} - 5 t\right) - 4 = 0$$
Detail solution
This equation is of the form
a*t^2 + b*t + c = 0

A quadratic equation can be solved
using the discriminant.
The roots of the quadratic equation:
$$t_{1} = \frac{\sqrt{D} - b}{2 a}$$
$$t_{2} = \frac{- \sqrt{D} - b}{2 a}$$
where D = b^2 - 4*a*c - it is the discriminant.
Because
$$a = 6$$
$$b = -5$$
$$c = -4$$
, then
D = b^2 - 4 * a * c = 

(-5)^2 - 4 * (6) * (-4) = 121

Because D > 0, then the equation has two roots.
t1 = (-b + sqrt(D)) / (2*a)

t2 = (-b - sqrt(D)) / (2*a)

or
$$t_{1} = \frac{4}{3}$$
$$t_{2} = - \frac{1}{2}$$
Vieta's Theorem
rewrite the equation
$$\left(6 t^{2} - 5 t\right) - 4 = 0$$
of
$$a t^{2} + b t + c = 0$$
as reduced quadratic equation
$$t^{2} + \frac{b t}{a} + \frac{c}{a} = 0$$
$$t^{2} - \frac{5 t}{6} - \frac{2}{3} = 0$$
$$p t + q + t^{2} = 0$$
where
$$p = \frac{b}{a}$$
$$p = - \frac{5}{6}$$
$$q = \frac{c}{a}$$
$$q = - \frac{2}{3}$$
Vieta Formulas
$$t_{1} + t_{2} = - p$$
$$t_{1} t_{2} = q$$
$$t_{1} + t_{2} = \frac{5}{6}$$
$$t_{1} t_{2} = - \frac{2}{3}$$
The graph
Sum and product of roots [src]
sum
-1/2 + 4/3
$$- \frac{1}{2} + \frac{4}{3}$$
=
5/6
$$\frac{5}{6}$$
product
-4 
---
2*3
$$- \frac{2}{3}$$
=
-2/3
$$- \frac{2}{3}$$
-2/3
Rapid solution [src]
t1 = -1/2
$$t_{1} = - \frac{1}{2}$$
t2 = 4/3
$$t_{2} = \frac{4}{3}$$
t2 = 4/3
Numerical answer [src]
t1 = 1.33333333333333
t2 = -0.5
t2 = -0.5