Part 1: Create an absolute value equation that has no solutions. Explain why this equation has no solutions. Part 2: Create an absolute value equation that has one solution. Explain why this equation has one solution. Part 3: Create an absolute value equation that has two solutions. Explain why this equation has two solutions.
In general, what do you know about |x|? What kinds of values can it have?
idk... infinte values?
Can it be negative, zero or positive?
any
No. It can never be negative.
For example, for what value of x is |x| = -1 ?
oohhhh
So given that, what's an answer to your first question?
I X I = -1 no absolute value can be negative
yes. Now the second?
I -9 I = 9 No matter what number it is... if its an absolute value its always positive
that's not an equation to requires a solution. You want something like | (an expression in x) | = (a number)
remember the definition: |x| = x, if x > 0 0, if x = 0 -x, if x < 0
but it would still be the same right? that no matter what number it is... if its an absolute value its always positive
yes. Let me ask you, how many solutions does |x| = 1 have?
2
oohhhh... ok thats the one with 2 solutions
So now you have an answer to part 3. What then is an answer to part 2?
I (an expression in x) I = (a number) No matter what number it is... if its an absolute value its always positive
|x| = -1 has no solutions |x| = 1 has two solutions |x| = (what?) has one solution.
0
Right. How many solutions does this equation have? |x+17| = 0
1
cause no matter positive or negative... it will always be 0
Yes, good. And how many does this one have? |2x+17| = -1
0 because its negative
yes. For the record, what is the solution of |x+17| = 0 ?
-17?
yes, good.
go back and have a look at the comments I wrote on your earlier questions. This one I think you've got under control now!
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