The invitations to a holiday party cost a total of $31.50 if each invitation cost $0.75 cents how many invitations were sent out

The lines shown below are parallel. if the green line has a slope of -1, what is the slope of the red line

Which ahows the graph of the solution set of 6x+4y< 12

According to modern science, earth is about 4.5 billion years old and written human history extends back about 10,000 years. suppose the entire history of earth is represented with a 10-meter-long timeline, with the birth of earth on one end and today at the other end.