Answer:Step-by-step explanation:We will write the equation in slope-intercept form since that's the easiest one to write from looking at a graph. The slope-intercept form of a line is y = mx + b, where m is the slope and b is the y-intercept.The "intercept" part of the equation comes from the y-intercept of the line. The y-intercept exists where x is 0...or in other words, where the line goes through the y-axis. Our line goes through the y-axis at a value of -1. So far we have y = mx - 1. Now we just need the slope.By looking at the line, we can determine the slope by using a slope triangle. This slope is negative, first off, since it goes "downhill". From the y-intercept of -1, we have to move down 1 unit and then to the right 1 unit in order to get to the next place on the graph where the line goes through where the grids of our graph cross. Down 1 unit is -1, and over to the right is +1, so rise/run is -1/+1 which is -1. That means our slope is -1. Therefore, the equation in slope-intercept form isy = -1x - 1 or just y = -x - 1.