Absolute Value of |-7+3| / value of y-x/8 for y=20, x=-4

John Whitaker

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May 9, 2006
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On a test:

#1. What is the Absolute Value of: |-7+3|? I answered: 10
It was marked wrong. I thought A/V removed all negative signs.

#2. y-x/8 where y=20 and x=-4. I answered: 2. It too, was marked wrong.
Thank you.
John Whitaker
 

galactus

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#1: \(\displaystyle |-7+3|=|-4|=4\)

#2: \(\displaystyle \frac{y-x}{8}=\frac{20-(-4)}{8}=\frac{24}{8}=3\)
 

stapel

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John Whitaker said:
I thought A/V removed all negative signs.
The absolute value makes the argument positive. But you still need to compute what that argument is. Only once you know what the insides simplify to, can you apply the sign change.

Eliz.
 

Denis

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Feb 17, 2004
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John Whitaker said:
#2. y-x/8 where y=20 and x=-4
The way you show it means y less x/8, or 20 - (-4/8) = 20 + 1/2 = 20.5
Was it bracketed on your test, like (y - x) / 8 ?
If so, see galactus'
 
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