Hello, I need help understanding how to do this problem.
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Answer: 26
Step-by-step explanation:so it takes 2 of 3x-1 to equal the whole thing 8x-20
2(3x-1)=8x-20
6x-2=8x-20
-6x. -6x
-2= 2x-20
+20=. +20
18= 2x
Divide by 2
9=X
BC= 3(9)-1=26