Answer:
$5.19
Step-by-step explanation:
→ Write the ratio
3 : 15.57
→ Divide both sides by 3
1 : 5.19
Answer:
put the right point at 80,12 and put the point on the left at 0,0
Step-by-step explanation:
Answer:
I think it is non proportional
Answer: 
<u>Step-by-step explanation:</u>

NOTE: The sign between 4x and 7 is missing in the question you posted. I assumed it was 4x + 7 in order to solve the equation.