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HELP PLEASE!!
Use the point and the slope to graph each line. Write the equation of the line

HELP PLEASE!! Use the point and the slope to graph each line. Write the equation of-example-1
User Lafor
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2 Answers

21 votes
21 votes

WHAT DO WE KNOW ABOUT PERPENDICULAR LINES ?

IS THAT WHEN THEIR GRADIENTS ARE MULTIPLIED THEY GIVE A PRODUCT OF -1.

TO FIND THE GRADIENT OF THE LINE PERPENDICULAR TO THE LINE WITH SLOPE/GRADIENT -1 WE CAN SAY


m1 * m2 = - 1 \\ - 1 * m2 = - 1 \\ m2 = 1

THIS MEANS THAT THE GRADIENT OF THE NEW LINE IS 1

the general equation of the straight line is y=mx+c


- 2 = 1(2) + c \\ - 2 = 2 + c \\ c = - 2 - 2 \\ c = - 4

This means that


y = 1x - 4 \\ simply \\ y = x - 4

User Akaspick
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2.4k points
13 votes
13 votes

Answer:

y = x in the slope intercept form

y - 2 = 1(x -2) in the point-slope form of a line

Explanation:

Perpendicular slopes are opposite reciprocals of each other. So the perpendicular slope would be 1.

We could write this in the point slope form of a line and the answer would be:

y - 2 = 1(x -2) This would be the point slope form of a line.

If you want your answer in the slope intercept form

y -2 = 1(x-2)

y - 2 = x - 2 Add two to both sides

y = x

User Just Lucky Really
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