mkg335:
"This always reminds me of '1984'... Uh, oh. 'Big Brother' is watching. lol
2+2 = 5? Fine with me. I'm not gonna be the one to 'dissent'... I mean, look what happened to Winston Smith!
I'm waaaaaay too young to become an unperson!"
But... to the concept "(for greater values of 2)" I totally understand this and we do watch out for 'estimation errors'. I know I'm not really telling you anything that you don't already know... but for just for fun..."
Absolute Value in Algebra means,
how far a number is from zero:
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"6" is 6 away from zero, and "−6" is also 6 away from zero.
So the absolute value of 6 is 6, and the absolute value of −6 is also 6
So...
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Solve |x+2|=5
Using "|u| = a is the same as u = ±a":
this: |
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|x+2|=5 |
is the same as this: |
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x+2 = ±5 |
Which will have two solutions:
x+2 = −5 |
x+2 = +5 |
x = −7 |
x = 3 (never 2)
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And here is the plot of |x+2|−5,
Try this one... "| x + 2 | < –1"
(every student gets burned on this one at least once... lol)
Now...Mixing Absolute Values and Inequalites needs a little care!
Here, the 'mathie' website Purplemath explains well how these inequities play out...
(doin' math before 7 am is better than waffles!)
'morning world!
xxMolly