Find the slope of a line perpendicular to each given line

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Hi Young Friend,

I show you another way for finding slop. If you have Ax+By+C=o that it is one of standard form for line.

It is enough, you find -A/B because it is slop.

3x+4y=8 3x +4y-8=0 slop = -3/4 as you know A=3 , B=4 . Now if you need slop for perpendicular line is

+4/3 and slop for parallel line is -3/4. In fact when two lines are parallel they have the same slop. I hope this explain is useful for you. Please feel free if you have any question.

Be successful,

Minoo

Hi Aaron;

The equation is currently in standard form...

Ax+By=C, A and B do not equal zero, and A is greater than zero.

The equation must be converted into slope-intercept form...

y=mx+b, m is the slope and b is the y-intercept, the value of y when x=0.

3x+4y=8

4y=-3x+8

y=[(-3/4)x]+2

The slope is -3/4. The slope of the line perpendicular to such is positive 4/3.

Dear Aaron,

3x + 4y = 8

4y = 8 - 3x

y = 2 - (3/4)x

So the slope of the given line is -(3/4).

The slope of any and all lines perpendicular to the given line is

-[1/(-3/4)] = 4/3

The slope of a line that is perpendicular to another line that has slope m is always -(1/m).

Take it to the bank.

Two lines are perpendicular if and only if their slopes are opposite reciprocals.

So if one line has a slope of 3/2, a line perpendicular to it must have a slope of -2/3

Or if one line has a slope of 5, a line perpendicular to it must have the slope -1/5

First rewrite you equation in slope-intercept form; that is one way to identify the slope. Then find its opposite reciprocal.

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## Comments

taking to the bank. But I have done some research, and Touba is correct. William and I had one oversight. When an equation is in standard form, as is this one, there is an easier technique to calculate slope. Slope is -A/B for an equation in the form of Ax+By=C. The slope of the line perpendicular to it is B/A. Thebankwill recognize that as legal tender.