Can someone please help me with these practice SAT math problems?

Test Preparation SAT Preparation
1

<p>From the blue book- </p>

<p>x:
2
3
4
5
6
7
8</p>

<p>f(x):
-1
0
2
-3
4
-5
6</p>

<p>(but in the book it's like a table...)
Several values of the function f are shown above. The function g is defined by g(x)=f(3x+1). What is the value of g(2)?</p>

<p>~</p>

<p>Any 2 points determine a line. If there are 6 points in a plane, no 3 of which lie on the same line, how many lines are determined by these 6 points?</p>

<p>~</p>

<p>Point A is a vertex oif an 8-sided polygon. The polygon has 8 sides of equal length and 8 angles of equal measure. When all possible diagonals are drawn from point A in the polygon, how many triangles are formed?</p>

<p>~</p>

<p>(x-8)(x-k) = (x^2)-5kx+m
In the equation above, k and m are constants. If the equation is true for all values of x, what is the value of m? </p>

<p>THANKS SO MUCH!</p>

2

<p>g(2) = f(3*2+1) = f(7) = -5</p>

<p>Try drawing 6 points arranged so that no 3 points are on the same line. It’s probably easiest to see if you draw a regular hexagon. Start from one vertex and connect the remaining vertices; Repeat with all other vertices. You will notice that each vertex has one line less to connect. 5+4+3+2+1 = 15</p>

<p>Octagons are formed by 6 triangles. It’s easy to see if you draw an octagon and connect one of the vertices (point A) to the other vertices.</p>

3

<ol>
<li>(x-8)(x-k) = (x^2)-5kx+m
Edit:
x^2-8x-kx+8k = x^2-5kx+m
(-8-k)=-5k
k= 2
8k = m
m = 8(2) = 16</li>
</ol>

4

<p>^ m is not 8. Look at post 3 by Jamesford at the thread below: </p>

<p><a href=“http://talk.collegeconfidential.com/sat-preparation/759503-2-math-problems-stumped-usual-800er.html[/url]”>http://talk.collegeconfidential.com/sat-preparation/759503-2-math-problems-stumped-usual-800er.html&lt;/a&gt;&lt;/p&gt;

5

<p>^Thanks for pointing that out. I would have got that if I foiled properly while typing >_>. I hope I don’t mess up something silly like that on the actual test.</p>