SOLUTION: Solve this system of equations using substitution. a + b + c = 180 ----------b = 3a ----------c = 5a

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Question 1049960: Solve this system of equations using substitution.
a + b + c = 180
----------b = 3a
----------c = 5a
Found 2 solutions by MathLover1, stanbon:
Answer by MathLover1(20850) About Me  (Show Source):
You can put this solution on YOUR website!

a+%2B+b+%2B+c+=+180....eq.1
----------b+=+3a....eq.2
----------c+=+5a....eq.3
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a+%2B+b+%2B+c+=+180....eq.1..........substitute b and c
a+%2B+3a+%2B+5a+=+180
9a+=+180
a+=+180%2F9
a+=+20
----------b+=+3a....eq.2...substitute 20 and fora
----------b+=+3%2A20
----------b+=+60

----------c+=+5a....eq.3...substitute 20 and fora
----------c+=+5%2A20
----------c+=+100


Answer by stanbon(75887) About Me  (Show Source):
You can put this solution on YOUR website!
Solve this system of equations using substitution.
a + b + c = 180
----------b = 3a
----------c = 5a
------
Substitute for "b" and "c"; solve for "a"::
a + 3a + 5a = 150
----------------------------
9a = 150
a = 50/3
------
b = 2a = 3(50/3) = 50
c = 5a = 5(50/3) = 250/3
--------
Cheers,
Stan H.
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