1/5(4-3x) = 1/7(3x-4)
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cross multiply 5 and 7
7(4-3x) = 5(3x-4)
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Distribute
28 - 21x = 15x - 20
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transpose 15x to the left and 28 to the right
-21x - 15x = -20 - 28
-36x = -48
x = 48/36
x = 4/3