solve the proportion
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Cross multiply
2x = 5(x - 3)
Expand
2x = 5x - 15
Subtract 5x from both sides
2x - 5x = -15
Simplify 2x 0 5x to -3x
-3x = -15
Divide both sides by -3
x = -15/-3
Two negatives make a positive
x = 15/3
Simplify 15/3 to 5
x = 5
You are correct.