Question 158149
(4,9);x+7y=5
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Begin my modifying the given equation into the slope-intercept form:
y = mx + b
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x+7y=5
7y=-x+5
y = (-1/7)x + 5/7
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From the above, we see that the slope of the line is -1/7.
We use the slope (-1/7) and the given point (4,9), and plug them into "point-slope" form:
y-y1 = m(x-x1)
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y - 9 = (-1/7)(x-4)
multiplying both sides by 7:
7y - 63 = (-1)(x-4)
7y - 63 = -x + 4
7y = -x + 67
finally, dividing both sides by 7:
y = (-1/7)x + 67/7  (this is what they're looking for)