Help...Blue Book Math

Test Preparation
1

<p>Since the Consolidated Blue Book Math thread has many problems from the earlier tests, I will post some problems from the later tests that I felt were hard. It would be great if someone could solve them. </p>

<li><p>Page 779
Let the function f be defined by f(x)=x^2 + 18. If m is a positive number such that f(2m)=2f(m), what is the value of m.</p></li>
<li><p>Page 795
The figure above shows part of a circle whose circumference is 45. If arcs of length 2 and length b continue to alternate around the entire circle so that there are 18 arcs of each length, what is the degree measure of each of the arcs of length B?
A- 4
B- 6
C- 10
D- 16
E-20</p></li>
<li><p>Page 807
Picture question about cubes</p></li>
<li><p>xy=7 and x-y=5, then x^2y - xy^2=
A=2
B=12
C=24
D=35
E=70</p></li>
</ol>

<p>Thanks a lot for helping me and later CC’ers who will need these answers/explanations to understand why they got it wrong and how to get it right.</p>

2

<p>16 on page 807 is quite intriguing, imo. I am very curious to hear the correct solution for it.</p>

3

<ol>
<li>pg. 779</li>
</ol>

<p>(2m)^2 + 18 = 2((m)^2 + 18)
4m^2 + 18 = 2m^2 + 36
2m^2 = 18
m^2 = 9
m = +/- 3, although they only have +3, b/c you cannot enter negative values in the student-produced answers section.</p>

4

<ol>
<li> (xy)(x-y) = x^2y - xy^2</li>
</ol>

<p>7*5=35. D.</p>

<ol>
<li> page 779
2m(squared)+36=4m(squared)+18
18=2m(squared)
9=m(squared)
m=3</li>
</ol>

<p>It's late and I have history to do, so i'll leave the others for someone else.</p>

5

<p>p795 #18</p>

<p>there are 18 arcs of length b and length 2, so:</p>

<p>36 + 18b = 45
-36 -36
18b = 9
9 represents 9/45 or 1/5 of the circle
1/5 * 360 = 72
18b = 72 degrees
/18 /18</p>

<p>b = 4 degrees, answer A</p>