Final answer:
The equation of the line parallel to y = -9 and passing through (7,3) is y = 3 in standard form.
Step-by-step explanation:
The line parallel to the line y = -9 can be represented by the equation y = mx + b, where m is the slope and b is the y-intercept. Since the given line has a slope of 0, the parallel line will also have a slope of 0. Therefore, the equation of the parallel line is y = 0x + b, which simplifies to y = b. Since the line passes through the point (7,3), we can substitute the coordinates of the point into the equation to find the value of b: 3 = b. Thus, the equation of the parallel line is y = 3, which is in standard form.