I need to know how to find the slope of a line using just a graph?

i have no equation to use, this is algebra 2. one of the points on the graph is (0, -1) this was not included but i gathered it from the graph. Can someone please help me?
Update: thank both of yall. the second one helped, even though i used the bottom one before i recieved the answers. :) thanx.<3
3 answers