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(4x-3)(4x+3)-(4x-1)=3x equation

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Numerical solution:

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The solution

You have entered [src]
(4*x - 3)*(4*x + 3) + -4*x + 1 = 3*x
$$\left(1 - 4 x\right) + \left(4 x - 3\right) \left(4 x + 3\right) = 3 x$$
Detail solution
Move right part of the equation to
left part with negative sign.

The equation is transformed from
$$\left(1 - 4 x\right) + \left(4 x - 3\right) \left(4 x + 3\right) = 3 x$$
to
$$- 3 x + \left(\left(1 - 4 x\right) + \left(4 x - 3\right) \left(4 x + 3\right)\right) = 0$$
Expand the expression in the equation
$$- 3 x + \left(\left(1 - 4 x\right) + \left(4 x - 3\right) \left(4 x + 3\right)\right) = 0$$
We get the quadratic equation
$$16 x^{2} - 7 x - 8 = 0$$
This equation is of the form
a*x^2 + b*x + c = 0

A quadratic equation can be solved
using the discriminant.
The roots of the quadratic equation:
$$x_{1} = \frac{\sqrt{D} - b}{2 a}$$
$$x_{2} = \frac{- \sqrt{D} - b}{2 a}$$
where D = b^2 - 4*a*c - it is the discriminant.
Because
$$a = 16$$
$$b = -7$$
$$c = -8$$
, then
D = b^2 - 4 * a * c = 

(-7)^2 - 4 * (16) * (-8) = 561

Because D > 0, then the equation has two roots.
x1 = (-b + sqrt(D)) / (2*a)

x2 = (-b - sqrt(D)) / (2*a)

or
$$x_{1} = \frac{7}{32} + \frac{\sqrt{561}}{32}$$
$$x_{2} = \frac{7}{32} - \frac{\sqrt{561}}{32}$$
The graph
Rapid solution [src]
            _____
     7    \/ 561 
x1 = -- - -------
     32      32  
$$x_{1} = \frac{7}{32} - \frac{\sqrt{561}}{32}$$
            _____
     7    \/ 561 
x2 = -- + -------
     32      32  
$$x_{2} = \frac{7}{32} + \frac{\sqrt{561}}{32}$$
x2 = 7/32 + sqrt(561)/32
Sum and product of roots [src]
sum
       _____          _____
7    \/ 561    7    \/ 561 
-- - ------- + -- + -------
32      32     32      32  
$$\left(\frac{7}{32} - \frac{\sqrt{561}}{32}\right) + \left(\frac{7}{32} + \frac{\sqrt{561}}{32}\right)$$
=
7/16
$$\frac{7}{16}$$
product
/       _____\ /       _____\
|7    \/ 561 | |7    \/ 561 |
|-- - -------|*|-- + -------|
\32      32  / \32      32  /
$$\left(\frac{7}{32} - \frac{\sqrt{561}}{32}\right) \left(\frac{7}{32} + \frac{\sqrt{561}}{32}\right)$$
=
-1/2
$$- \frac{1}{2}$$
-1/2
Numerical answer [src]
x1 = 0.958919955145438
x2 = -0.521419955145438
x2 = -0.521419955145438