Help me with this its the picture i put down below

The jewelry store is having a sale. necklaces that were regularly priced at $23.50 are on sale for $18.80. what is the percentage of decrease in the price of necklaces?

[10 points, algebra 2]according to my answer key the restrictions are -1 and 4. but why not positive 1?

Hell . what are the solutions to `10x^2 - 38x - 8 = 0`? is this when i find the factors and use the numbers within the factors to determine the zeros? i hope that made sense lol