Final answer:
To write the equation in slope-intercept form with a slope of -1 and a y-intercept of 3, the equation is y = -1x + 3, which represents a line that decreases by one unit for every one unit increase in x and crosses the y-axis at 3.
Step-by-step explanation:
To write an equation in slope-intercept form, which is y = mx + b, we use the given slope (m) and the y-intercept (b). The student has provided the slope, m = -1, and the y-intercept, b = 3. Thus, plugging these values into the slope-intercept form yields the equation:
y = -1x + 3
This equation tells us that for every one unit increase in x, the value of y decreases by one unit because the slope is negative. The line crosses the y-axis at 3, which is the y-intercept.