How to solve this quadratic equation?

  • #1
SunnyBoy123
New user has been reminded to use the Homework Help Template and show their work in the first post
Ok so what am I doing wrong, when i try to put equation 300 = (x+3)(x+2)(1) into Stanford form I get x^2 + 5x - 294 = 0.

http://imgur.com/a/N9E83
 

Answers and Replies

  • #2
Ray Vickson
Science Advisor
Homework Helper
Dearly Missed
10,706
1,722
Ok so what am I doing wrong, when i try to put equation 300 = (x+3)(x+2)(1) into Stanford form I get x^2 + 5x - 294 = 0.

http://imgur.com/a/N9E83

There is no such thing as a "Stanford form", but there can be a "standard form". Anyway, you have re-written the equation correctly.
 
  • #3
lewando
Homework Helper
Gold Member
1,352
138
The equation that you have correctly re-written is wrong.
 
  • #4
Ray Vickson
Science Advisor
Homework Helper
Dearly Missed
10,706
1,722
The equation that you have correctly re-written is wrong.

This is probably very confusing to the OP. You are literally saying that the equation ##(x+2)(x+3) = 300## is wrong, because that is the equation he re-wrote. In fact, the equation is correct and his re-write of it is also correct; the book's re-write is wrong.
 
Last edited:
  • #5
lewando
Homework Helper
Gold Member
1,352
138
The equation that you have correctly re-written is wrong.
Sorry--upon re-read this is unclear. My intent was to encourage him to look upstream a bit more.
 
  • #6
SammyS
Staff Emeritus
Science Advisor
Homework Helper
Gold Member
11,377
1,038
Ok so what am I doing wrong, when i try to put equation 300 = (x+3)(x+2) (1) into Stanford standard form I get x^2 + 5x - 294 = 0.
The two equations you have above are equivalent.

The problem is with the expression given for the width of the box. The length and width of the box are each 2 inches less than the length and width of the metal sheet, respectively.

So the width of the box should have been given as ##\ W=x-2\ ##.

d4Fv4vQ.jpg
 

Related Threads on How to solve this quadratic equation?

  • Last Post
Replies
2
Views
2K
Replies
21
Views
3K
  • Last Post
Replies
21
Views
2K
  • Last Post
Replies
2
Views
2K
  • Last Post
Replies
2
Views
2K
  • Last Post
Replies
6
Views
894
Replies
15
Views
1K
Replies
10
Views
2K
  • Last Post
Replies
3
Views
2K
  • Last Post
Replies
8
Views
2K
Top