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7x+|-10+2x|x=-4 equation

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Numerical solution:

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The solution

You have entered [src]
7*x + |-10 + 2*x|*x = -4
$$x \left|{2 x - 10}\right| + 7 x = -4$$
Detail solution
For every modulo expressions in the equation
allow cases, when this expressions ">=0" or "<0",
solve the resulting equation.

1.
$$2 x - 10 \geq 0$$
or
$$5 \leq x \wedge x < \infty$$
we get the equation
$$x \left(2 x - 10\right) + 7 x + 4 = 0$$
after simplifying we get
$$x \left(2 x - 10\right) + 7 x + 4 = 0$$
the solution in this interval:
$$x_{1} = \frac{3}{4} - \frac{\sqrt{23} i}{4}$$
but x1 not in the inequality interval
$$x_{2} = \frac{3}{4} + \frac{\sqrt{23} i}{4}$$
but x2 not in the inequality interval

2.
$$2 x - 10 < 0$$
or
$$-\infty < x \wedge x < 5$$
we get the equation
$$x \left(10 - 2 x\right) + 7 x + 4 = 0$$
after simplifying we get
$$x \left(10 - 2 x\right) + 7 x + 4 = 0$$
the solution in this interval:
$$x_{3} = \frac{17}{4} - \frac{\sqrt{321}}{4}$$
$$x_{4} = \frac{17}{4} + \frac{\sqrt{321}}{4}$$
but x4 not in the inequality interval


The final answer:
$$x_{1} = \frac{17}{4} - \frac{\sqrt{321}}{4}$$
The graph
Sum and product of roots [src]
sum
       _____
17   \/ 321 
-- - -------
4       4   
$$\frac{17}{4} - \frac{\sqrt{321}}{4}$$
=
       _____
17   \/ 321 
-- - -------
4       4   
$$\frac{17}{4} - \frac{\sqrt{321}}{4}$$
product
       _____
17   \/ 321 
-- - -------
4       4   
$$\frac{17}{4} - \frac{\sqrt{321}}{4}$$
=
       _____
17   \/ 321 
-- - -------
4       4   
$$\frac{17}{4} - \frac{\sqrt{321}}{4}$$
17/4 - sqrt(321)/4
Rapid solution [src]
            _____
     17   \/ 321 
x1 = -- - -------
     4       4   
$$x_{1} = \frac{17}{4} - \frac{\sqrt{321}}{4}$$
x1 = 17/4 - sqrt(321)/4
Numerical answer [src]
x1 = -0.229118216792229
x1 = -0.229118216792229