Adjacent Angles Property: Can Two Obtuse Angles Share a Side?

Adjacent Angles with Linear Pair Constraints

It is possible for two adjacent angles to be obtuse.

❤️ Continue Your Math Journey!

We have hundreds of course questions with personalized recommendations + Account 100% premium

Step-by-step video solution

Watch the teacher solve the problem with clear explanations
00:00 Is it possible for adjacent angles to both be obtuse?
00:03 Adjacent angles form a straight angle (sum to 180)
00:11 Let's assume both are larger than a right angle (90)
00:20 Their sum would necessarily be greater than 180
00:23 Therefore, it's impossible for both angles to be obtuse
00:26 And this is the solution to the question

Step-by-step written solution

Follow each step carefully to understand the complete solution
1

Understand the problem

It is possible for two adjacent angles to be obtuse.

2

Step-by-step solution

To determine if two adjacent angles can both be obtuse, we first need to recall the definition of an obtuse angle and what it means for angles to be adjacent.

  • An obtuse angle measures more than 9090^\circ but less than 180180^\circ.
  • Adjacent angles are two angles that share a common side and vertex.
  • When we consider adjacent angles that form a linear pair, their sum must equal 180180^\circ.

For two angles to both be obtuse, each must measure more than 9090^\circ. Let's consider two angles, aa and bb, that are adjacent and both obtuse:

  • a>90a > 90^\circ
  • b>90b > 90^\circ

Adding both inequalities gives:

a+b>180a + b > 180^\circ

This sum a+ba + b would contradict the requirement that adjacent angles forming a linear pair sum to exactly 180180^\circ.

Therefore, two adjacent angles cannot both be obtuse, as their sums would exceed the allowable amount for a linear pair.

Thus, it is not possible for two adjacent angles to be obtuse. The correct answer is False.

3

Final Answer

False

Key Points to Remember

Essential concepts to master this topic
  • Definition: Adjacent angles share a common vertex and side
  • Rule: Linear pair angles must sum to exactly 180180^\circ
  • Check: Two obtuse angles: 91° + 91° = 182° > 180° ✓

Common Mistakes

Avoid these frequent errors
  • Forgetting that adjacent angles form linear pairs
    Don't assume adjacent angles can have any measure = ignores the 180° sum rule! This leads to impossible angle combinations. Always remember that adjacent angles forming a linear pair must add to exactly 180°.

Practice Quiz

Test your knowledge with interactive questions

If one of two corresponding angles is a right angle, then the other angle will also be a right angle.

FAQ

Everything you need to know about this question

What exactly makes two angles adjacent?

+

Two angles are adjacent when they share a common vertex and a common side, but don't overlap. Think of them as sitting right next to each other!

Can adjacent angles ever both be obtuse?

+

No! Since obtuse angles are greater than 90°, two of them would add up to more than 180°. But adjacent angles in a linear pair must equal exactly 180°.

What's the largest an adjacent angle can be if the other is obtuse?

+

If one angle is obtuse (say 91°), the other must be 89° or less to keep their sum at 180°. So the other angle must be acute!

Do all adjacent angles have to sum to 180°?

+

Only when they form a linear pair (on a straight line). Other adjacent angles around a point sum to 360°, but linear pairs always sum to 180°.

How can I remember this rule?

+
  • Think of a straight line = 180°
  • Two obtuse angles = both > 90°
  • 90° + 90° = 180°, so anything larger breaks the rule!

🌟 Unlock Your Math Potential

Get unlimited access to all 18 Parallel and Perpendicular Lines questions, detailed video solutions, and personalized progress tracking.

📹

Unlimited Video Solutions

Step-by-step explanations for every problem

📊

Progress Analytics

Track your mastery across all topics

🚫

Ad-Free Learning

Focus on math without distractions

No credit card required • Cancel anytime

More Questions

Click on any question to see the complete solution with step-by-step explanations