The opening bid was 175.
Work Step by Step
Let X represent the amount of the opening bid. Since X is the opening bid, three times the opening bid means 3 $\times$ X = 3X. 35 more than three times the opening bid means 3X + 35. The set of wheels were sold for 560. So, we set up the equation: 3X + 35 = 560 Subtract 35 from both sides 3X = 525 Divide both sides by 3 X = 175