Answer:
y = (2/3)x + 9
Explanation:
Equation of a straight line is y = mx + b. You are trying to finish the equation. 
Note that: 
m = slope = 2/3
b = y-intercept = 9
Plug in the corresponding numbers to the corresponding variables: 
y = mx + b --> y = (2/3)x + 9
y = (2/3)x + 9 is your equation. 
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