Melody

do the substitution, get the values then go to a factor calculator to get any common factors.

You can use the web2.0calculator  

If you want the facors of 20 say, you'd put in     

factor(20)  and press =

 {2, 3, 5, 5, 5, 6, 6, 6}

all the same   

666       1

555        1

2 the same

665       3

663        3

662        3

556        3

553        3

552       3

All different

235         3!=6

236         3!=6

356         3!=6

2+18+18 = 38

What did you get?

I would be interested to see someones approach as well 

x=t-3

so   y=x+3

Substitute that into the second equation and you have your non-parametric form

Tidy it up for into standard form.

Do that and come back with what you have done.

If you want help how about presenting your question properly.

Put the stuff between the dollar signs into a LaTex box.

Just by visual inspection.

If  x=8          = 8mod 9

If  x=8          = 2 mod 6

x=18k +8

Initially Ben had 9x dollars and  John has 4x dollars.   

Ben spends  $63 so now   Ben has  9x-63   dollars and  John still has  4x dolllars.

This is in the ration 1:2

so

\(\frac{9x-63}{1}=\frac{4x}{2}\\ 9x-63=2x\\ 7x=63\\ x=9\)

You can finish it :)