Posted by Angel on Wednesday, March 23, 2011 at 10:13pm.
6n219n+15=o
(the 2 is an exponent)
idk how 2 do it
the teacher told us how but didn't show us
plz help

math  Reiny, Wednesday, March 23, 2011 at 10:20pm
6n^2  19n + 15 = 0
factors to
(3x5)(2x3) = 0
so 3x5 = 0 or 2x3 = 0
x = 5/3 or x = 3/2 
math  Angel, Wednesday, March 23, 2011 at 10:20pm
ty

math  Jai, Wednesday, March 23, 2011 at 10:29pm
6n^219n+15=0
to solve this we can either factor it (if it's factorable) or use quadratic formula,, here we just use quadratic formula:
for a given quadratic equation, ax^2 + bx + c = 0,
x = [b + sqrt(b^2  4*a*c)]/(2*a)
note: + is plus or minus
where
a = numerical coeff of x^2,
b = numerical coeff of x and
c = constant
in the problem,
6n^219n+15=0 (note that x is just replaced by the x variable)
a = 6
b = 19
c = 15
then we substitute it to quadratic formula:
x = [b + sqrt(b^2  4*a*c)]/(2*a)
x = [(19) + sqrt((19)^2  4*6*15)]/(2*6)
we can separate it into plus and minus:
using plus:
x = [(19) + sqrt((19)^2  4*6*15)]/(2*6)
x = [19 + sqrt(361360)]/(12)
x = [19 + sqrt(1)]/12
x = (19 + 1)/12
x = 5/3 (this is the first root)
for the minus:
x = [(19)  sqrt((19)^2  4*6*15)]/(2*6)
x = [19  sqrt(1)]/12
x = 18/12
x = 3/2 (second root)
*note: variable x here is also n
hope this helps~ :) 
math  Bella, Wednesday, March 23, 2011 at 10:34pm
lol thx both of yall an srry but i change names cuz ppl alwayz think angel is my real name an its not so i change it 2 make sure ppl dnt do that