SOLUTION: Hello, How do I write an equation for this: Perpendicular to the graph of 4x-y=12 and passes through (8,2) Thank you

Algebra ->  Graphs -> SOLUTION: Hello, How do I write an equation for this: Perpendicular to the graph of 4x-y=12 and passes through (8,2) Thank you      Log On


   

Question 101509: Hello,

How do I write an equation for this:

Perpendicular to the graph of 4x-y=12 and passes through (8,2)

Thank you
Found 2 solutions by elima, MathLover1:
Answer by elima(1433) About Me  (Show Source):
You can put this solution on YOUR website!
Perpendicular to the graph of 4x-y=12 and passes through (8,2)
The slopes of Perpendicular lines are negative reciprocals;
first lets put the equation in standard form;
4x-y=12
-y=-4x+12
y=4x-12; so the slope of this line is 4;
The slope of the perpendicular line is -1%2F4
Now that we have the slope we use the point-slope form to find the equation;
y-y1=%28-1%2F4%29%28x-x1%29
y-2=%28-1%2F4%29%28x-8%29
y-2=-%281%2F4%29x%2B2
y=-%281%2F4%29x%2B2%2B2
y=-%281%2F4%29x%2B4; equation of perpendicular line
:)

Answer by MathLover1(20855) About Me  (Show Source):
You can put this solution on YOUR website!
From 4x-y=12 we can see that slope m=4
Therefore the perpendicular line has slope m1=-%281%2F4%29
If you use the+point – slope+form%29, you will have:
y=+-%281%2F4%29%28x-8%29+%2B+2+ now you can simplify it
y=-%281%2F4%29%2Ax+%2B+%28-1%2F4%29%28-8%29+%2B2
y=+-%281%2F4%29%2Ax+%2B2+%2B2
y=+-%281%2F4%29%2Ax+%2B4