how do i write an equation from a graph

Question

how d i get an equation from a graph with a line and a slope but the slope is not given

Answer 1

Adding on to Justin, once you get the slope, substitute any set of coordinates into the equation (y=mx+b, where m is slope and b is the intercept) to find the value of the intercept. Equation done!

Answer 2

If you have two points on a line then you do (Y2-Y1)/(X2-X1) That will give you the slope of the two points. If you have multiple points then you need to do the (sum of all X*Y)/(the sum of all X^2)