Solve using a system of Equations with two unknowns:

[lightfight]

Solve using a system of Equations with two unknowns: A candy jar contains 50 red and green jelly beans. THe number of red jelly beans is one less than twice the number of green jelly beans. How many of each color are in the jar?

I tried setting this up as:
R + G = 50
R(2G - 1) + G = 50

but I can't figure out how to solve it since I keep getting 2RG, which I have no idea what to do with. How am I supposed to set up the equations?

 

[pka]

This R(2G - 1) + G = 50 should be 2G-1=R.

 

[lightfight]

I thought of that but then can I just rearrange the problem?

i.e. R + G = 50
2G - 1 = R

to

R + G= 50
-R + 2G=1

so I'd get 3G=51 so G = 51/.3 and then go back and substitute. Is that right?

 

[Denis]

I thought of that but then can I just rearrange the problem?
i.e. R + G = 50
2G - 1 = R
to
R + G= 50
-R + 2G=1
so I'd get 3G=51 so G = 51/.3 and then go back and substitute. Is that right?

Yes; G = 51/3 = 17 ; why do you have 51/.3 ?

You could also do this by substituting R = 2G - 1 in the 1st equation:
2G - 1 + G = 50
3G = 51
G = 17