Midpoint Theorem on Right-angled Triangle

Here we will prove that in a right-angled triangle the median drawn to the hypotenuse is half the hypotenuse in length.

Solution:

Given: In ∆PQR, ∠Q = 90°. QD is the median drawn to hypotenuse PR.

Midpoint Theorem on Right-angled Triangle

To prove: QS = \(\frac{1}{2}\)PR.

Construction: Draw ST ∥ QR such that ST cuts PQ at T.

Proof:

            Statement

             Reason

1. In ∆PQR, PS = \(\frac{1}{2}\)PR.

1. S is the midpoint of PR.

2. In ∆PQR,

(i) S is the midpoint of PR

(ii) ST ∥ QR

2.

(i) Given.

(ii) By construction.

3. Therefore, T is the midpoint of PQ.

3. By converse of the Midpoint Theorem.

4. TS ⊥ PQ.

4. TS ∥ QR and QR ⊥ PQ

5. In ∆PTS and ∆QTS ,

(i) PT = TQ

(ii) TS = TS

(iii) ∠PTS = ∠QTS = 90°.

5.

(i) From the statement 3.

(ii) Common side.

(iii) From the statement 4.

6. Therefore, ∆PTS ≅ ∆QTS.

6. By SAS criterion of congruency.

7. PS = QS.

7. CPCTC

8. Therefore, QS = \(\frac{1}{2}\)PR.

8. Using statement 7 in statement 1.







9th Grade Math

From Midpoint Theorem on Right-angled Triangle 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