Help with a math question.

Test Preparation SAT Preparation
1

<p>Hi all.</p>

<p>I am working really hard on math for Nov 4 Sat. I have a math question about triangle length. The answer, in my view, just seems wrong.</p>

<p>View</a> image: Screen Shot 2012 10 23 at 12 14 26 AM</p>

<p>I know that if I have a triangle with one length of 4 and the other of 10. I know that the 3rd can only be 6<x<14. Because 10-4 =6 and 10+4=14. In this question. 400 is equal and smaller. I can understand why it is smaller, but how can it be equal?</p>

<p>Thank you all.</p>

2

<p>the link seems wrong
it is not working</p>

3

<p>Hello Amy2525.</p>

<p>The link seems fine. Still, I uploaded it to another site.</p>

<p><a href=“http://i50.■■■■■■■.com/10mrmtk.png[/url]”>http://i50.■■■■■■■.com/10mrmtk.png&lt;/a&gt;&lt;/p&gt;

<p>Thank you</p>

4

<p>Choice E is incorrect. It’s greater and NOT greater or equal.</p>

5

<p>

</p>

<p>Except that “*a *> b” is still true when *a *is strictly greater than b. E may not be the narrowest true statement possible, but it’s not false.</p>

6

<p>Please ignore. Double post.</p>

7

<p>Sorry. I am still trying to understand it, but something just doesn’t seem right.</p>

<p>Lets say that A is 4 and b is 18. I know that length C (20 in the picture) can only be 14<x<22. Or if A=B and a is 11, so it can only be 0<x<22. </p>

<p>Sikorsky, can you please give an example to your comment. I just don’t understand it.</p>

<p>Thank you</p>

8

<p>E is technically correct, because “400 ≤ (a+b)^2” includes the “strictly less than” case, “400 < (a+b)^2.”</p>

<p>For example, 12 is greater than 7, so 12 > 7. But 12 ≥ 7 is also true.</p>

9

<p>Exactly as rspence said, if x < y, then it’s also true that x < y.</p>

<p>Think about it: x couldn’t possibly be less than y and equal to y at the same time, right? It has to be one or the other. So “x < y” is just mathematical shorthand for, “Either x is less than y, or else x equals y.” And if either piece of that or statement is true, then logically the whole statement is true.</p>

<p>(NOTE: in math, or usually means “one or the other or both.” But the Comparison Property of Real Numbers states that for any two real numbers a and b, exactly one of the following statements is true: a < b, or *a *= b, or a > b. So in the case of “less than or equal to,” the or has to mean “one or the other, but not both.”)</p>

10

<p>Thank you guys.</p>

<p>I understand this logic, and will keep this in mind in other questions.</p>