Coplanar planes and point lines
Answer:
1
Step-by-step explanation:
The first step is to understand what the integrand looks like. (See the graph below.)
It is -1 for x < 0 and +1 for x > 0. Thus, the value of this integral is ...

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Essentially, you treat the absolute value as a piecewise linear function. This is the same way you treat an absolute value in any equation or inequality.
Here, this means you divide the integral into two parts: one where the integrand is -x/x, and one where it is +x/x.
Each input should only have 1 output. Multiple inputs can have the same output, but one input can only correspond to a single output.
Also, if you graph the relation with the input as the x coordinate and output as the y coordinate, you can then conduct a verical line test. Anywhere you draw a vertical line, you should only intersect the curve one time.
2x-8=x+4
Get the x to the other side and the 8 to the opposite
2x-x=4+8
X=12