<PRE><B>Question 424749</B>
180 = A + B + C
B = 5A
C = 4A - 2

plug in B and C into first equation
180 = A + 5A + (4A - 2)
add like terms
180 = 10A - 2
add two to both sides
182 = 10A
divide by 10
A = 91/5
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