For slope m and point (h, k), the equation of a line in point-slope form is
y - k = m(x - h)
You are given m = 1/2 and (h, k) = (6, -3), so your line has equation
y +3 = (1/2)(x - 6)
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In slope-intercept form, this is
y = (1/2)x -6
In standard form, this is
x - 2y = 12
