Question 968769
A = 3B
A +5 = 2(B +5)
A +5 = 2B +10
now substitute for A = 3B
3B +5 = 2B +10
subtract 2B form both sides of =
B +5 = 10
B = 5 and A = 15
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check answer by substituting for A and B in the second equation
15 +5 = 2(5+5)
20 = 20
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