Answer: 4
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Step-by-step explanation:
For now, let's call the y intercept b
We'll plug in x = 2 and y = 3 from the given point to find b
y = mx+b
y = (-1/2)x + b
3 = (-1/2)*2 + b
3 = -1 + b
3+1 = b
4 = b
b = 4
The y intercept is 4
The equation of the line is y = (-1/2)x + 4