Final answer:
The question is solving for the equation of a straight line with a slope of 3 that also passes through the point (-3,9). The correct equation of the line, based on the given slope and point, is y = 3x + 9. This linear equation can be graphed to represent a line with a three-fold rise over run.
Step-by-step explanation:
The question is about finding the equation of a straight line that has a slope of 3 and passes through the point (-3,9). The general form of the equation of a straight line is y = mx + b, where m is the slope and b is the y-intercept. To find the equation of our line, we know that the y-intercept is 9, since that is the y-value when x is 0, and the slope is given as 3. Thus, the equation of the line is y = 3x + 9. This line graph would show a rise of 3 units in the y-direction for every 1 unit increase in the x-direction.
To confirm that this line passes through the point (-3,9), we can substitute x with -3 into the equation and check if y equals 9. Following this, we get y = 3(-3) + 9, which simplifies to y = -9 + 9, and we find that y indeed equals 9, matching our given point. Therefore, the equation y = 3x + 9 is the correct one for the line passing through the point (-3,9).