# GCSE maths factorisation

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#1
how would you factorise 3r^2 + 2n^2 - 10/3*n*r to make it equal r or n
0
16 years ago
#2
that's an expression, you can't make anything equal anything in an expression. you need two expressions with a common relationship to make an equation.
0
#3
how would you factorise 3r^2 + 2n^2 - 10/3*n*r = 0 to make it equal r or n
0
16 years ago
#4
(Original post by silent p......?)
how would you factorise 3r^2 + 2n^2 - 10/3*n*r = 0 to make it equal r or n
well,to make life easier u can multiply everything by 3...........
0
16 years ago
#5
(Original post by silent p......?)
how would you factorise 3r^2 + 2n^2 - 10/3*n*r = 0 to make it equal r or n
Are you trying to solve the equation and find values of r and n?

And which one is the right equation?

3r^2 + 2n^2 - (10/3)(n)(r) = 0

OR

3r^2 + 2n^2 - 10/(3nr) = 0
0
#6
r or n and

3r^2 + 2n^2 - (10/3)*nr = 0
0
16 years ago
#7
(Original post by silent p......?)
r or n and

3r^2 + 2n^2 - (10/3)*nr = 0
multiply by 3 to get 9r^2 + 6n^2 -10nr=0,which errrr cannot be simplified to (an+br)(cn+dr)=0
0
#8
it's impossible?
0
16 years ago
#9
(Original post by silent p......?)
it's impossible?
sorry to break it 2 ya 0
16 years ago
#10
(Original post by silent p......?)
r or n and

3r^2 + 2n^2 - (10/3)*nr = 0
9r² - 10nr +6n² = 0

r = [10n+-√(100n²-216n)]/18
OR
n = [10r +-√(100r²-216r)]/12

this only works for 0 >= n,r or n,r >= 2.16
0
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