Answer:
To find the slope of a line in the form y + mx = b, where m is the slope and b is the y-intercept, we can solve for y to obtain y = -mx + b.
For the equation y + 3x = 7, we can solve for y by subtracting 3x from both sides to get y = -3x + 7. Therefore, the slope of this line is -3.
To find the slope of a line parallel to this line, we know that parallel lines have the same slope. Therefore, any line that is parallel to y + 3x = 7 will also have a slope of -3.
To find the slope of a line perpendicular to this line, we know that perpendicular lines have negative reciprocal slopes. Therefore, the slope of a line perpendicular to y + 3x = 7 will be the negative reciprocal of -3, which is 1/3.
In summary, the slope of the line y + 3x = 7 is -3. Any line parallel to this line will also have a slope of -3, and any line perpendicular to this line will have a slope of 1/3.