Bisectors of the Angles of a Parallelogram form a Rectangle

Here we will prove that the bisectors of the angles of a parallelogram form a rectangle.

Given: PQRS is a parallelogram in which PQ ∥ SR and SP ∥ RQ. The bisectors of ∠P, ∠Q, ∠R and ∠S are PJ, QK, RL and SM respectively which enclose the quadrilateral JKLM.

To prove: JKLM is a rectangle.

Proof:

            Statement

            Reason

1. ∠QPS + ∠PSR = 180°

Therefore, \(\frac{1}{2}\)∠QPS + \(\frac{1}{2}\)∠PSR = 90°

1. PQ ∥ SR.

2. ∠SPM + ∠PSM = 90°

2. PJ and SM are bisectors of ∠QPS and ∠PSR respectively.

3. ∠PMS = 90°       ⟹ JM ⊥ ML.

3. Sum of the three angles of ∆PSM is 180°.

4. Taking bisectors of ∠S and ∠R, ML ⊥ LK;

Taking bisectors of ∠R and ∠Q, KL ⊥ JK;

Taking bisectors of ∠Q and ∠P, JK ⊥ JM.

4. Similarly.

5. JK ∥ ML, JM ∥ KL.

5. Two lines perpendicular to the same line are parallel.

6. JKLM is a parallelogram. (Proved).

6. By statement 5 and one angle, say ∠JML = 90°.





9th Grade Math

From Bisectors of the Angles of a Parallelogram form a Rectangle 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. Subtraction of Decimals | Subtracting Decimals | Decimal Subtraction

    Apr 17, 25 01:54 PM

    We will discuss here about the subtraction of decimals. Decimals are subtracted in the same way as we subtract ordinary numbers. We arrange the digits in columns

    Read More

  2. Addition of Decimals | How to Add Decimals? | Adding Decimals|Addition

    Apr 17, 25 01:17 PM

    We will discuss here about the addition of decimals. Decimals are added in the same way as we add ordinary numbers. We arrange the digits in columns and then add as required. Let us consider some

    Read More

  3. Expanded form of Decimal Fractions |How to Write a Decimal in Expanded

    Apr 17, 25 12:21 PM

    Expanded form of Decimal
    Decimal numbers can be expressed in expanded form using the place-value chart. In expanded form of decimal fractions we will learn how to read and write the decimal numbers. Note: When a decimal is mi…

    Read More

  4. Math Place Value | Place Value | Place Value Chart | Ones and Tens

    Apr 16, 25 03:10 PM

    0, 1, 2, 3, 4, 5, 6, 7, 8 and 9 are one-digit numbers. Numbers from 10 to 99 are two-digit numbers. Let us look at the digit 6 in the number 64. It is in the tens place of the number. 6 tens = 60 So…

    Read More

  5. Place Value and Face Value | Place and Face Value of Larger Number

    Apr 16, 25 02:55 PM

    Place Value of 3-Digit Numbers
    The place value of a digit in a number is the value it holds to be at the place in the number. We know about the place value and face value of a digit and we will learn about it in details. We know th…

    Read More