Advertisements
Advertisements
Question
If one of the four angles formed by two intersecting lines is a right angle, then show that
each of the four angles is a right angle.
Advertisements
Solution
Given,
AB and CD are two lines intersecting at O such that
`∠`BOC = 90°
`∠`AOC = 90°, `∠`AOD = 90° and `∠`BOD = 90°
Proof:
Given that `∠`BOC = 90°
Vertically opposite angles are equal

`∠`BOC = `∠`AOD = 90°
`∠`AOC, `∠`BOC are Linear pair of angles
`∠`AOC + `∠`BOC = 180° [LinearPair]
⇒`∠`AOC + 90° = 180°
⇒ `∠`AOC = 90°
Vertically opposite angles
∴ `∠`AOC = `∠`BOD = 90°
Hence, `∠`AOC = `∠`BOC = `∠`BOD = `∠`AOD = 90°
APPEARS IN
RELATED QUESTIONS
In the below fig, rays AB and CD intersect at O.
Determine y when x = 60°

In the below fig, rays AB and CD intersect at O
Determine x when y =40

In the given figure, the value of x is ______.

In the given figure, which of the following statements must be true?
(i) a + b = d + c
(ii) a + c + e = 180°
(iii) b + f = c + e

Give two examples of parallel lines you can see in your environment.
Look at the picture given below. Decide whether the lines given in picture is parallel or perpendicular to each other and write the answer in the box.

Look at the picture given below. Decide whether the lines given in picture is parallel or perpendicular to each other and write the answer in the box.

What is the geometric relationship between two straight lines in the same plane that will never intersect, no matter how much they are extended?
Which phrase correctly describes the distance between two parallel lines?
Which symbolic notation correctly represents the statement 'Line m is parallel to Line n?'
