In slope-intercept form, we have these values (y = mx + b):
m = slope
b = y-intercept
Change the equation from standard form to slope-intercept form.
-9x + 7y = 28
-9x + 9x + 7y = 28 + 9x
7y = 28 + 9x
7y/7 = 28/7 + 9x/7
y = 4 + 9/7x
y = 9/7x + 4
Therefore, the y-intercept is 4.
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