An experiment consists of flipping a fair coin four times. what is the probability of obtaining at least one head?

Evaluate the dot product of (3,-1) and (1,5)

Lizette is training for a marathon. at 7: 00 she left her house and ran until 8: 30, then she walked until 11: 30. she covered a total distance of 18 miles. her running speed was six miles per hour faster than her walking speed. find her running and walking speeds in miles per hour.

Atriangle has side lengths of x, x+11, and 3x+5. what is the perimeter?