SOLUTION: A+B=10 C/D=4 A+C=3 B+D=9

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Question 1159602: A+B=10
C/D=4
A+C=3
B+D=9
Found 3 solutions by Alan3354, josgarithmetic, greenestamps:
Answer by Alan3354(69443) About Me  (Show Source):
You can put this solution on YOUR website!
Do you have a question?

Answer by josgarithmetic(39617) About Me  (Show Source):
You can put this solution on YOUR website!
You should say what kind of method you need to use.

system%28A%2BB=10%2CC=4D%2CA%2BC=3%2CB%2BD=9%29

system%28A%2BB=10%2CA%2B4D=3%2CB%2BD=9%29, A=10-B;

system%2810-B%2B4D=3%2CB%2BD=9%29

system%28-B%2B4D=-7%2CB%2BD=9%29

system%28B-4D=7%2CB%2BD=9%29-----------this much by just a couple of substitutions. You can solve this for B and D, right? You can then finish on your own for A and C?

Answer by greenestamps(13200) About Me  (Show Source):
You can put this solution on YOUR website!


(1) From the second given equation, C = 4D.

(2) Add the last two given equations to get A+B+C+D = 12. Then since the first equation tells us A+B=10, we know C+D = 2.

(3) Now substitute the result from (1) in (2). 4D+D = 2. D = 2/5.

Once you have the value of that one variable, it will be easy to find the values of the others.