Posted by asdf on Friday, December 31, 2010 at 4:08am.
I have a number of problems I'm having problem with but they start with the example given in the book
2x^2  10x
=2(x^2  5x)
=2{[x(5/2)]^2  [(5/2)^2]}
=2[x(5/2)]^2  (25/2)
Why isn't (5/2)^2 (25/4)?
I'm struggling with the exercises as well.
3x^2  24x
I get 3(x4)^2  16 or if I try to follow the example, 3(x4)^2  32, but the answer at the back of the book is 3(x4)^2  48

Math; Complete the square for the expressions  asdf, Friday, December 31, 2010 at 4:10am
I meant, "Why isn't (25/2)^2 (25/4)?"

Math; Complete the square for the expressions  drwls, Friday, December 31, 2010 at 7:09am
You seem to have forgotten a basic rule of multiplying fractions.
a/b * c/d = ac/(bd)
The square of any fraction a/b is a^2/b^2.
For example, 2/3 of 2/3 = (2/3)^2 = 4/9
and (25/2)^2 = 625/4
Looking at your second problem,
3x^2  24x
= 3(x^2 8x) Now add and subtract 48
= 3(x^2 8x +16) 48
= 3(x4)^2 48
Answer This Question
Related Questions
 Fib. Number  I noticed someone else is having problems with the same problem ...
 College Math II  Show a complete solution to each problem. Find the exact ...
 Math Homework  1) Given the side of a square pyramid is 6cm and the altitude is...
 College Algebra  I need some help with a handful of questions. I need to see ...
 College Algebra  I need some help with a handful of questions. I need to see ...
 College Algebra help please  I need some help with a handful of questions. I ...
 Algebra 2  could you walk me thorugh these problems simplfy square root 18  3 ...
 3rd grade  Good evening ~ I have 2 questions. Kelsey was assigned math homework...
 Math Algebra 1  i was wondering if anyone could help me on this problem. expand...
 Math  Having a problem writing an expanded number in notation in descending ...
More Related Questions