Final answer:
The lines represented by the equations 3y+4x=-21 and 15y+20x=-60 are parallel to each other because they have the same slope.
Step-by-step explanation:
The lines represented by the equations 3y+4x=-21 and 15y+20x=-60 are parallel to each other. This is because the two equations have the same slope. To find the slope, we can rewrite the equations in slope-intercept form.
- 3y = -4x - 21
- y = (-4/3)x - 7
- 15y = -20x - 60
- y = (-20/15)x - 4
The slopes of both equations are -4/3 and -20/15, which are equal. Therefore, the lines represented by the equations are parallel.