Cant figure it out pls help

5y = -3x + 7
y = -3/5x + 7/5
Parallel = same slope
y = -3/5x + b
3 = -3/5 + b, b = 18/5
Standard form: Ax + By = C
y = -3/5x + 18/5
-3/5x - y = -18/5
Multiply by -5
Solution: 3x + 5y = 18
Answer: Scale factor = 2
This is the same as writing [tex]\frac{2}{1}[/tex]
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Explanation:
Focus on the left sides of each triangle. They correspond to one another. Note how RS represents the first two letters of RST; while MN represents the first two letters of MNO. We can see the order matters.
To find the scale factor, we divide MN over RS to get
MN/RS = 6/3 = 2
Therefore, the sides of triangle MNO are 2 times longer compared to the sides of triangle RST.
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Extra info:
If you want to find x, then you would solve the following
MN/RS = ON/TS
6/3 = x/5.5
6*5.5 = 3x
33 = 3x
3x = 33
x = 33/3
x = 11
or we could simply multiply ST = 5.5 by the scale factor 2 getting 5.5*2 = 11, which is the length of segment ON.