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How do you get from x= 5a - 3n to show n - a = (2n - x)/5?

,

Can't see how to get from x = 5a - 3n

to show

n - a =

\frac{2n - x}{5}

Reply 1

Slowbro93

Split the -3n term, can you see where to go next? :smile:

Reply 2

davros

Original post by jessieboo77

,

Can't see how to get from x = 5a - 3n

to show

n - a =

\frac{2n - x}{5}

Alternative method:

(2n - x)/5 = (2n/5) - (x/5)

From your original eq, x/5 = a - (3n/5) so from here you can work out what (2n/5) - (x/5) is :smile:

Reply 3

jessieboo77

Thanks for the help :smile:

.

x = 5a - 3n

x + n = 5a - 2n

2n - 5a = -x - n

3n - 5a = -x

5n - 5a = 2n - x

divide by 5

n - a = (2n - x) / 5

Woo :cool:

Reply 4

pezhman

2X+Y=100. What is the highest result of the equation?
Could any body help me ? Thanks
Using optimising and differentiation.

Reply 5

davros

Original post by pezhman

2X+Y=100. What is the highest result of the equation?
Could any body help me ? Thanks
Using optimising and differentiation.

Please don't hijack other people's threads - it's more polite to start your own in future :smile:

As it stands you can make X and Y as big as you like by adjusting the other one! Do you have some other constraints e.g. X and Y must be positive, or integers, or something?