completing the square?

  • 0 votes

how do you complete the square if you've got a number before your x^2?? :)

Posted Mon 30th May, 2011 @ 11:42 by Kelly:)

1 Answer

  • 1 vote

Say your question is to complete the square for this formula: 2x^2 - 8x - 10,

You can factorise this such that the new equation would be 2 [x^2 - 4x - 5]

From there, you can complete the square of the formula within the brackets:

2 [x^2 - 4x - 5] = 

2 [(x - 2)^2 - 4 - 5] = 

2 [(x - 2)^2 - 9]

Hope this helps ;)

Answered Mon 30th May, 2011 @ 11:59 by Sagz
Edited by Sagz on Mon 30th May, 2011 @ 12:00