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(|2*x-7|)=8 equation

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Numerical solution:

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The solution

You have entered [src]
|2*x - 7| = 8
$$\left|{2 x - 7}\right| = 8$$
Detail solution
For every modulo expressions in the equation
allow cases, when this expressions ">=0" or "<0",
solve the resulting equation.

1.
$$2 x - 7 \geq 0$$
or
$$\frac{7}{2} \leq x \wedge x < \infty$$
we get the equation
$$\left(2 x - 7\right) - 8 = 0$$
after simplifying we get
$$2 x - 15 = 0$$
the solution in this interval:
$$x_{1} = \frac{15}{2}$$

2.
$$2 x - 7 < 0$$
or
$$-\infty < x \wedge x < \frac{7}{2}$$
we get the equation
$$\left(7 - 2 x\right) - 8 = 0$$
after simplifying we get
$$- 2 x - 1 = 0$$
the solution in this interval:
$$x_{2} = - \frac{1}{2}$$


The final answer:
$$x_{1} = \frac{15}{2}$$
$$x_{2} = - \frac{1}{2}$$
The graph
Sum and product of roots [src]
sum
-1/2 + 15/2
$$- \frac{1}{2} + \frac{15}{2}$$
=
7
$$7$$
product
-15 
----
2*2 
$$- \frac{15}{4}$$
=
-15/4
$$- \frac{15}{4}$$
-15/4
Rapid solution [src]
x1 = -1/2
$$x_{1} = - \frac{1}{2}$$
x2 = 15/2
$$x_{2} = \frac{15}{2}$$
x2 = 15/2
Numerical answer [src]
x1 = 7.5
x2 = -0.5
x2 = -0.5