Answer:
[tex]y = 3x - 6[/tex]
Step-by-step explanation:
A linear function has the following format:
[tex]y = ax + b[/tex]
In which a is the slope(rate of change) and b is the y-intercept, that is, the value of y when x = 0.
Rate of change of 3
This means that [tex]a = 3[/tex]
So
[tex]y = 3x + b[/tex]
A solution at (6, 12).
This means that when x = 6, y = 12. So
[tex]y = 3x + b[/tex]
[tex]12 = 3*6 + b[/tex]
[tex]b = -6[/tex]
The linear function is:
[tex]y = 3x - 6[/tex]
