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

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Numerical solution:

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The solution

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

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

2.
$$x^{2} + 7 x < 0$$
or
$$-7 < x \wedge x < 0$$
we get the equation
$$- 4 x + \left(- x^{2} - 7 x\right) - 10 = 0$$
after simplifying we get
$$- x^{2} - 11 x - 10 = 0$$
the solution in this interval:
$$x_{3} = -10$$
but x3 not in the inequality interval
$$x_{4} = -1$$


The final answer:
$$x_{1} = 2$$
$$x_{2} = -1$$
The graph
Sum and product of roots [src]
sum
-1 + 2
$$-1 + 2$$
=
1
$$1$$
product
-2
$$- 2$$
=
-2
$$-2$$
-2
Rapid solution [src]
x1 = -1
$$x_{1} = -1$$
x2 = 2
$$x_{2} = 2$$
x2 = 2
Numerical answer [src]
x1 = 2.0
x2 = -1.0
x2 = -1.0