The graph appears to cross the y-axis at y=1. This is the y-intercept. Expressed as an ordered pair, the point is (x, y) = (0, 1).
The graph appears to cross the x-axis at x=5. That means the line has dropped one unit (from y=1 to y=0) while x has increased by 5 units (from x=0 to x=5). The slope is ...
... slope = (change in y)/(change in x) = (-1)/(5) = -1/5
The slope is -1/5.
The y-intercept is 1.
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The slope-intercept from of the equation for the line is
... y = (-1/5)x +1