How many solutions does the equation below have?
∣ ∣ ∣ ∣ ∣ x − 8 ∣ − 1 0 ∣ − 4 ∣ − 5 ∣ − 1 ∣ = 0
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Nice and simple! :)
∣ ∣ x − 8 ∣ − 1 0 ∣ with y = 4 marked in yellow.
∣
∣
∣
x
−
8
∣
−
1
0
∣
−
4
∣
with
y
=
5
in yellow.
∣ ∣ ∣ ∣ x − 8 ∣ − 1 0 ∣ − 4 ∣ − 5 ∣ with y = 1 in yellow.
∣ ∣ ∣ ∣ ∣ x − 8 ∣ − 1 0 ∣ − 4 ∣ − 5 ∣ − 1 ∣
How are all the graphs plotted? Must we resort to computers to get the answer?
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The reason I used drawings was to show the behavior of the function. The plots were done using Microsoft Word, painstakingly and without math software of any kind.
The solution method itself could have been done with graph paper, no need for computer.
Do you mean " y =4 marked in yellow", " y =5 marked in yellow", and " y =1 marked in yellow" ?
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Yes, I am on my way out the door going on a full night search and rescue mission, way too much to think about.
@Marta Reece - Interesting to see a graphical view of a solution, gives me a different perspective on it. My solution was exactly that of @Shourya Pandey , i.e., purely algebraic. Thanks for taking the time to do the graphics. I appreciate how much effort it takes.
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Thank you. I tend to do my solving of many problems visually, and frequently find it difficult to explain to others. I am glad to hear when I have succeeded. Thanks again.
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∣ ∣ ∣ ∣ ∣ x − 8 ∣ − 1 0 ∣ − 4 ∣ − 5 ∣ − 1 ∣ = 0
⟺ ∣ ∣ ∣ ∣ x − 8 ∣ − 1 0 ∣ − 4 ∣ − 5 ∣ = 1
⟺ ∣ ∣ ∣ x − 8 ∣ − 1 0 ∣ − 4 ∣ = 6 or 4
⟺ ∣ ∣ x − 8 ∣ − 1 0 ∣ = − 2 , 1 0 , 0 or 8 , but − 2 is discarded , obviously
⟺ ∣ x − 8 ∣ = 0 , 2 0 , 1 0 , 2 or 1 8
⟺ x = 8 , − 1 2 , 2 8 , − 2 , 1 8 , 6 , 1 0 , − 1 0 or 2 6 , i.e., there are 9 possible values of x .