T O P I C R E V I E W 
Haven 
Posted  09/22/2008 : 13:35:48 I am having a problem figuring out a problem in the SAT Study Guide on page 599 problem number 18.
The problem states that ABCD is a rectangle and that Points 'A' and 'C' lie on the graph of y = px, where p is a constant.
In the problem which is drawn as a graph, point 'A' is located in the third quadrant at (1/2, A); point 'B' is located in the second quadrant at (1/2, B); point 'C' is located in the first quadrant at (1/2, C); and point 'D' is located in the fourth quadrant at (1/2, d ).
The problem further states that if the area of ABCD is 4, what is the value of p?
I need to know how to find the value of 'p'.
I would also like to know what area of mathematics I should look at in order to better understand this type of problem?
any help would be greatly appreciated.

4 L A T E S T R E P L I E S (Newest First) 
Haven 
Posted  09/23/2008 : 13:30:17 Thank You Very Much Subhotosh Khan. 
Subhotosh Khan 
Posted  09/23/2008 : 07:18:12 Now about the problem.
Since it is a rectangle (and pair of vertices have same xcoordinate)
A = D
and
B = C......................................(1)
Then
AB = B  A and
AD = 1
Area = 4 = 1*(B  A) ........................(2)
using (1) in (2)
C  A = 4....................................(3)
A & C lie on y = px^3
so
A = p/8......................................(4)
and
C = p/8.......................................(5)
Use (3), (4) & (5) to solve for 'p'.

Haven 
Posted  09/22/2008 : 19:35:33 I stand corrected, the x coordinate in the "D" quadrant should be positive 1/2.
Thanks,
Haven Williams

Subhotosh Khan 
Posted  09/22/2008 : 14:05:06 quote: Originally posted by Haven
I am having a problem figuring out a problem in the SAT Study Guide on page 599 problem number 18.
The problem states that ABCD is a rectangle and that Points 'A' and 'C' lie on the graph of y = px, where p is a constant.
In the problem which is drawn as a graph, point 'A' is located in the third quadrant at (1/2, A); point 'B' is located in the second quadrant at (1/2, B); point 'C' is located in the first quadrant at (1/2, C); and
point 'D' is located in the fourth quadrant at (1/2, d ). <<< How is this x coordinate negative  in fourth quadrant the x coordinates should be positive.
The problem further states that if the area of ABCD is 4, what is the value of p?
I need to know how to find the value of 'p'.
I would also like to know what area of mathematics I should look at in order to better understand this type of problem?
any help would be greatly appreciated.


