X= -5 because you divide -5x by -5 to get x alone so you have to 25/-5 which is -5
Answer:
9=x
Step-by-step explanation:
Let x be the old price
X= 1200$
The price decreased 20% after 1 year to become price y :
Y= 0.8x
= 0.8 (1200)
= 960$
In the year after y also decreased 20% to be price y’:
Y’= 0.8y
= 0.8 (960)
= 768 $
The price y’ then decreased 20% to become price y’’:
Y’’ = 0.8 y’
= 0.8 (768)
= 614.4 $
Then the price will be 614.4 $ after 3 years
-3x+5y=-4
5y=3x-4
Y=3/5x-4/5
When it parallel to the line y=3/5x-4/5
It can be y=-3/5x+b
-5=6/5+b
B=-5-6/5=-25/5-6/5=-31/5
Y=-3/5x-31/5
3/5x+y=-31/5
Multiply 5
3x+5y=-31