I hope it helps you get it right
Answer: 9
Step-by-step explanation:

6x+3y=-9
3y = -6x - 9
y = -2x - 3 ; This line has slope = -2
Parallel lines, slope is the same so the slope of a line that is parallel to
6x+3y = - 9 is also -2
Answer
-2
Answer:
Dryer = 320
Washer = 960
Step-by-step explanation:
Washer + Dryer = 1280
Let,
Dryer = x
Washer = 3x
3x + x = 1280
4x = 1280
x = 320
Washer = 3x = 3(320)=960
960 + 320 = 1280
Thus,
Dryer = 320
Washer = 960
<u><em>~lenvy~</em></u>