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Grade 12th passAnalytical Geometry

Find the equation of the sides of a triangle having (4,-1) as a vertex and the lines x – 1 = 0 and x – y – 1= 0 are the equations of internal ange bisectors of its sides.

Profile image of Krishna Thapa
5 Years agoGrade 12th pass
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ApprovedApproved Tutor Answer1 Year ago

To find the equations of the sides of a triangle with a vertex at (4, -1) and given internal angle bisectors, we need to analyze the provided lines and their relationships to the triangle's sides. The lines given are x – 1 = 0, which is a vertical line at x = 1, and x – y – 1 = 0, which can be rearranged to y = x - 1. These lines will help us determine the angles and slopes of the triangle's sides.

Identifying the Angle Bisectors

The line x = 1 is vertical, indicating that one of the angles of the triangle is formed by a side that runs horizontally or at an angle intersecting this line. The second line, y = x - 1, has a slope of 1, meaning it rises one unit vertically for every unit it moves horizontally. This line will bisect an angle formed by two sides of the triangle.

Finding the Sides of the Triangle

Let’s denote the vertex of the triangle as A(4, -1). We need to find the equations of the other two sides, which we can denote as lines AB and AC. The angle bisector x = 1 suggests that one of the sides (let's say AB) must be horizontal or vertical, while the other side (AC) will be influenced by the slope of the line y = x - 1.

  • Equation of Side AB: Since the angle bisector x = 1 is vertical, we can assume that side AB is horizontal. Therefore, the equation of side AB can be written as y = -1, which passes through point A(4, -1).
  • Equation of Side AC: The angle bisector y = x - 1 suggests that side AC will have a slope of 1. We can use point-slope form to find the equation of this line. The point-slope form is given by y - y1 = m(x - x1), where (x1, y1) is point A and m is the slope.

Calculating the Equation of Side AC

Using point A(4, -1) and the slope of 1:

y - (-1) = 1(x - 4)

y + 1 = x - 4

Rearranging this gives:

y = x - 5

Final Equations of the Triangle's Sides

Now we have the equations for two sides of the triangle:

  • Side AB: y = -1
  • Side AC: y = x - 5

Next, we need to find the third side, BC. Since we have established that the angle bisector x = 1 is vertical, side BC must also be vertical. Therefore, the equation of side BC can be given as:

x = 1

Summary of the Triangle's Side Equations

In conclusion, the equations of the sides of the triangle with vertex A(4, -1) and the specified angle bisectors are:

  • AB: y = -1
  • AC: y = x - 5
  • BC: x = 1

These equations represent the three sides of the triangle, with the vertex at (4, -1) and the specified angle bisectors. This methodical approach allows us to visualize and understand the relationships between the angles and sides of the triangle effectively.