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Is there a solution to the following equation?
4 | x - 3 | + 1 = 1​

Is there a solution to the following equation? 4 | x - 3 | + 1 = 1​-example-1
User MemphiZ
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1 Answer

4 votes

Answer: x = 3 (choice A)

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Work Shown

4|x-3| + 1 = 1

4|x-3| = 1-1

4|x-3| = 0

|x-3| = 0/4

|x-3| = 0

x-3 = 0

x = 3

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Check:

Plug in x = 3 and simplify.

4|x-3| + 1 = 1

4|3-3| + 1 = 1

4*|0| + 1 = 1

4*0 + 1 = 1

0 + 1 = 1

1 = 1

We arrive at a true statement, so the first equation is true when x = 3.

The solution x = 3 has been confirmed.

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Let's see what happens if we plugged in x = 4

4*|x-3| + 1 = 1

4*|4-3| + 1 = 1

4*|1| + 1 = 1

4*1 + 1 = 1

4 + 1 = 1

5 = 1

The last statement is false, so the original equation is false when x = 4.

We rule out x = 4 as a solution.

You should find that x = 6 leads to a false equation as well, so x = 6 isn't a solution either.

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Another way to check is to use graphing software like GeoGebra or Desmos.

Plot the equation y = 4*abs(x-3)+1 where the "abs" refers to "absolute value". Also plot the horizontal line y = 1.

The two intersect at exactly one point and it is (3,1). The x coordinate of this intersection is the final answer.

User Yannisl
by
8.5k points