Answer: 
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Work Shown:
Part 1

Part 2

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Explanations:
- There are quite a bit of steps. I decided to break things into two parts.
- The goal is to get x all by itself on its own side, which is why I subtracted (x-n)/n from both sides in part 1, step 2. I also subtracted p from both sides.
- Afterward, I gave each fraction the LCD mn. I multiplied top and bottom of the first fraction by n/n. I did a similar operation to the second fraction, but with m instead.
- From there, we distribute and simplify. The mn terms cancel on the left side numerator (second step of part 2).
- The n≠m is there to prevent the denominator (n-m) from being zero. We cannot divide by zero.
- If the formulas don't properly display, then you might have to refresh the page.
Answer:
Midpoint (9,1,(8-4) = (8.5, -1.5)
step-by step:Midpoint (9,1, 8-4)=(xA+xB2,yA+yB2)=(9+82,1+−42)=(172,−32)Midpoint of a line segment (9,1, 8-4)= (8.5, -1.5)
The sale price would be $7.70. the sale is 30%off, so the discount would be o.3 x 11. The sale price itself would be 0.7 x 11. Therefore, 0.7x11 is $7.70 and that is the sale price