In the diagram, which must be true for point d to be an orthocenter?

James was playing a game with his friends. he won 35 points. then he lost 15, lost 40 and won 55. how did he come out

Math it's appreciated. (picture provided)

Adecibel is a logarithmic unit that can be used to measure the intensity of a sound. the function y = 10logx gives the intensity of a sound in decibels, where x is the ratio of the intensity of the sound to a reference intensity. the reference intensity is generally set at the threshold of hearing. use the graphing utility to graph the decibel function.a whisper has a sound intensity of 30 decibels. use your graph to you complete the following statement. the sound intensity of a whisper is times the reference intensity.