Which system of equations below has exactly one solution?
y = -8x - 6 and y = -8x + 6
y=-8x – 6 and ay = -4x - 3
y = -8% - 6 and y = 8x - 6
y=-8x - 6 and -y = 8x + 6

Solve for x i'll try to attach the files bc it's not letting me for some reason

10 ! a train starts from grand city and travels toward belleville 388 miles away. at the same time, a train starts from belleville and runs at the rate of 47 miles per hour toward grand city. they pass each other 4 hours later. find the rate of the train from grand city.

At the electronics store you have a coupon for 20% off up to 2 cds you buy for cds with the original cost of $10.99 each the sales tax is 5% what is the total cost of your purchase