Hello Ang,
Let x represent the amount of sales in a week. The straight commission offer (0.02x) will be at least as good as the second companies offer (0.01x + 290) when the weekly sales satisfies the following inequality:
0.02x ≥ 0.01x + 290
Subtracting 0.01x on both sides yields,
0.01x ≥ 290
Dividing by 0.01 results in,
x ≥ 29000
Hence, you would have to sell at least $29,000 worth of product in order for the straight commission offer to be at least as good as the second company's offer.