<PRE><B>Question 1091804</B>
5x + y = 9
:
y = -5x +9
:
the slope of this line is -5, therefore the perpendicular line is the negative reciprocal of -5 which is 1/5
:
y = x/5 +b
:
to find b, we use the point (4,7)
:
7 = 4/5 +b
:
b = 7 -4/5 = 35/5 -4/5 = 31/5
:
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y = x/5 +31/5
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:
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