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Question
Find the values of x, y, z if :-
5x + 20y + 50z = 500
&
x + y + z = 20

Answer
Questioner:Prateek
Country:India
Category:Advanced Math
Private:No
Subject:Maths
Question:

Find the values of x, y, z if :-
5x + 20y + 50z = 500
&
x + y + z = 20
...................................
Sincy you have two equations and three variables, you will need a parameter.

Start by reducing:

5x + 20y + 50z = 500
to

x + 4y + 10z = 100  (you could have done that)
Take x + y + z = 20  and solve:

x = 20 - y - z

Substitute:

(20 - y - z) + 4y + 10z = 100

3y + 9z = 80

Now set z = t  (it could be y, and you could choose any parameter) and

1. Solve for y in terms of t.
2. Go back and solve for x in terms of t.

Done.

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