Chord and Tangent Intersect Externally

Here we will prove that if a chord and a tangent intersect externally then the product of the lengths of the segments of the chord is equal to the square of the length of the tangent from the point of contact to the point of intersection.

Given: XY is a chord of a circle and TZ is a tangent that touches the circle at T. XY is produced to cut the tangent TZ at Z.

Chord and Tangent Intersect Externally

To prove: XZ × YZ = TZ2.

Construction: Join T to X and Y.

Proof:

Statement

Reason

1. In ∆XTZ and ∆YTZ,

(i) ∠XZT = ∠YZT

(ii) ∠TXZ = ∠YTZ

1.

(i) Common angle.

(ii) Angle between chord and tangent is equal to the angle in the alternate segment.

2. In ∆XTZ ∼ ∆YTZ

2. By AA criterion for similarity.

3. \(\frac{XZ}{TZ}\) = \(\frac{TZ}{YZ}\) ⟹ XZ × YZ = TZ^2 (proved).

3. Corresponding sides of similar triangles are proportional.





10th Grade Math

From Chord and Tangent Intersect Externally to HOME PAGE




Didn't find what you were looking for? Or want to know more information about Math Only Math. Use this Google Search to find what you need.



New! Comments

Have your say about what you just read! Leave me a comment in the box below. Ask a Question or Answer a Question.

Share this page: What’s this?

Recent Articles

  1. Word Problems on Area and Perimeter | Free Worksheet with Answers

    Jul 26, 24 04:58 PM

    word problems on area and perimeter

    Read More

  2. Worksheet on Perimeter | Perimeter of Squares and Rectangle | Answers

    Jul 26, 24 04:37 PM

    Most and Least Perimeter
    Practice the questions given in the worksheet on perimeter. The questions are based on finding the perimeter of the triangle, perimeter of the square, perimeter of rectangle and word problems. I. Find…

    Read More

  3. Perimeter and Area of Irregular Figures | Solved Example Problems

    Jul 26, 24 02:20 PM

    Perimeter of Irregular Figures
    Here we will get the ideas how to solve the problems on finding the perimeter and area of irregular figures. The figure PQRSTU is a hexagon. PS is a diagonal and QY, RO, TX and UZ are the respective d…

    Read More

  4. Perimeter and Area of Plane Figures | Definition of Perimeter and Area

    Jul 26, 24 11:50 AM

    Perimeter of a Triangle
    A plane figure is made of line segments or arcs of curves in a plane. It is a closed figure if the figure begins and ends at the same point. We are familiar with plane figures like squares, rectangles…

    Read More

  5. 5th Grade Math Problems | Table of Contents | Worksheets |Free Answers

    Jul 26, 24 01:35 AM

    In 5th grade math problems you will get all types of examples on different topics along with the solutions. Keeping in mind the mental level of child in Grade 5, every efforts has been made to introdu…

    Read More