John Whitaker
Junior Member
- Joined
- May 9, 2006
- Messages
- 89
I have:
2x^2 + 12x + 3 = 0 (divide by 2)
x^2 + 6x + 3/2 = 0
x^2 + 6x = - 3/2
X^2 + 6x + 9 = 15/2
(x + 3 )^2 = 15/2
x + 3 = +/- sqrt (15/2)
x + 3 = +/- sqrt (30)/2
My question is: What arithmatical process determines that:
= +/- sqrt (15/2) should become +/- sqrt (30)/2
Please explain how the "30" comes in. Thank you.
2x^2 + 12x + 3 = 0 (divide by 2)
x^2 + 6x + 3/2 = 0
x^2 + 6x = - 3/2
X^2 + 6x + 9 = 15/2
(x + 3 )^2 = 15/2
x + 3 = +/- sqrt (15/2)
x + 3 = +/- sqrt (30)/2
My question is: What arithmatical process determines that:
= +/- sqrt (15/2) should become +/- sqrt (30)/2
Please explain how the "30" comes in. Thank you.