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The value of a truck is $24,000 when it is brand new. The value depreciates $900 per year. when will the value of the car be less than $17,000? write an inequality to represent the situation, do not solve the inequality, defined the variable.

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Answer:

after 8 years

24,000 - 900x < 17,000

the variable is x, the number of years

Explanation:

One way is to just subtract 900 from 24000 until it gets to 17000.

1. 23,100

2. 22,200

3. 21,300

4. 20,400

5. 19,500

6. 18,600

7. 17,700

8. 16,800

Another way is to write an inequality.

I know you don't have to solve it, but I'm going to write it anyway.

24,000 - 900x < 17,000

24,000 is the total, or what you start with

900 is what goes down every year

x is the number of years

all of that has to be less than 17,000

To put this into words, it would be: if 24,000 minus $900 times the number of years is less than 17000, what is x?

To find the answer, first find the difference between 24000 and 17000

subtract 2400 from each so so you are left with:

-900x < -7,000

Then to find x, the number of years, divide both sides by -900:

x < 7.777...

since that is the exact answer, and we don't really need that, we can round it up to 8.

x < 8

To learn to do this might be troublesome, but its way faster in the end. I'm not the best at explaining math, but hope this helps :)

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