Steps to solve:
0.3x = 15
~Divide 0.3 to both sides
0.3x/0.3 = 15/0.3
~Simplify
x = 50
This is a vertical line so the slope is undefined.
The line passes through the point (50, 0) and there is no y-intercept since its a straight vertical line.
Best of Luck!
Plug in 4 for x and solve equation like so. c=2
Answer:

Decimal Form:

Step-by-step explanation:

Remove Parentheses: 

Multiply the numbers: 

Divide both sides by: 

Simplify:

Hope I helped. If so, may I get brainliest and a thanks?
Thank you, have a good day! =)