SOLUTION: confused. Write the equation of the line in standard form which passes through (-9,3) perpendicular to x-3y=0

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Question 884928: confused.
Write the equation of the line in standard form which passes through (-9,3) perpendicular to x-3y=0
Answer by josgarithmetic(39617) About Me  (Show Source):
You can put this solution on YOUR website!
x-3y=0
x=3y
y=x%2F3, the slope is %281%2F3%29.

The slope you want for the line perpendicular to x-3y=0 must be -3. The slopes for perpendicular lines in a plane must be negative reciprocals.

Using SLOPE-INTERCEPT FORM, you want an equation y=-3x%2Bb and you do not yet know b. You know that the line must pass through (-9,3).
y%2B3x=b
Substitute the coordinate values.
b=3%2B3%28-9%29
b=3-27
b=-24
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Equation in slope-intercept form still, is y=-3x-24.
Convert that into standard form.