5x^2 + 12x + 3 = 0
A: -12 +- sqrt (21) / 5
B: -6 +- sqrt (21) / 10
C: -6 +- sqrt (21) / 5
D: -6 +- sqrt (51) / 5
2006-12-12 14:22:05 · 6 answers · asked by quickhitboy 2 in Education & Reference ➔ Homework Help
Here's a link on the formula. All you have to do is plug and chug....
http://www.purplemath.com/modules/quadform.htm
2006-12-12 14:30:15 · answer #1 · answered by mdetaos 3 · 0⤊ 0⤋
Well, The quadratic formula is [(-b +- sqrt(b^ - 4ac)] / 2a
In the equation 5x^2 + 12x + 3 = 0
a = 5
b = 12
c = 3
[-12 +- sqrt(144 - (4*5*3))] / 2(5)
[-12 +- sqrt(84)] / 10
[-12 +- (2 *sqrt(21)] / 10
Then, divide through by 2
[-6 +- sqrt(21)] / 5 => C.
2006-12-12 22:32:24 · answer #2 · answered by Rachel 1 · 0⤊ 0⤋
C: -6 +- sqrt (21) / 5
2006-12-13 16:25:56 · answer #3 · answered by m6 2 · 0⤊ 0⤋
I thought the Quadratic Formula was A sqrd + B sqrd = C sqrd
Where the heck did D come from?
Just when I felt secure in helping my kids with their homework . . .
2006-12-12 22:31:06 · answer #4 · answered by Sassygirlzmom 5 · 0⤊ 0⤋
-B +- sqrt (B^2 - 4ac)/2a
plug in the numbers with a calculator
2006-12-12 22:33:26 · answer #5 · answered by thank you come again 2 · 0⤊ 0⤋
I figured it all out on paper and got all excited when it matched answer C then I see that Rachel got to it first. Either way I second her opinion ;)
2006-12-12 22:35:40 · answer #6 · answered by jacque_sue89 3 · 0⤊ 0⤋