Sorry it’s the best quality photo I could get
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Explanation:
The idea is to isolate y getting it by itself. We can do this a number of ways, but possibly the quickest way is to add y to both sides
x/2 - y + 6 = 0
x/2 + 6 = 0+y
x/2 + 6 = y
y = x/2 + 6
This is now in slope intercept form, more or less. We could rewrite the x/2 as (1/2)x to get
y = (1/2)x + 6
Then compare this to y = mx+b and note the slope is m = 1/2 and the y intercept is b = 6.
Side note: the quality of the snapshot is fairly good. I've seen much worse.