Which one would be more beneficiary, High school diploma cles or Ged program?

I signed up for a online cl to earn my high school diploma but have to pay between 300-600 dollars. I only paid 30 dollars, so before I go any farther what should I do? The Ged program is free and I can study at home at my own pace. I can study at home for my HS diploma but it's not at my own pace. And all the tests are open book. But Im scared if I cant get some of the math formulas because Ive been out of school for 7 years I will fail and loose my money. Their are tutors that I can call and talk to but Im kind of nervous. But I do know that colleges prefer a high school diploma . PLEaSe help me.