the equations of perpendicular bisectors of the sides AB and AC of a triangle ABC are x-y+5=0 and x+2y=0 respectively.If this point A(1,-2) the equation of the line BC is

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- October 19th 2011, 11:33 AMprasumperpendicular bisector
the equations of perpendicular bisectors of the sides AB and AC of a triangle ABC are x-y+5=0 and x+2y=0 respectively.If this point A(1,-2) the equation of the line BC is

- October 19th 2011, 01:24 PMPlatoRe: perpendicular bisector
Step 1. Find the point, D, where those two lines intersect.

Step 2. Find the distance, d(A,D). The is the circum-radius.

Step 3. Write the equations of the two lines through A each of which is perpendicular to one of the given lines

Step 4. Find the points on the lines in step 3 where the circum-circle insects.

Step 5: Those points are B & C. - October 19th 2011, 01:46 PMearbothRe: perpendicular bisector
1. Since the line AC has the slope . Use point-slope-formula to determine the equation of

2.

Consequently the midpoint of is

Now you can determine the coordinates of point C:

3. The same method will give you the point B:

4. Use the coordinates of B and C to determine the equation of BC.