September 20, 2022

Vertical Angles: Theorem, Proof, Vertically Opposite Angles

Studying vertical angles is a crucial subject for everyone who wishes to study arithmetic or another subject that uses it. It's tough work, but we'll make sure you get a handle on these theories so you can make the grade!

Don’t feel discouraged if you don’t recollect or don’t understand these theories, as this blog will teach you all the fundamentals. Additionally, we will help you understand the secret to learning faster and enhancing your scores in mathematics and other common subjects today.

The Theorem

The vertical angle theorem expresses that at any time two straight lines meet, they create opposite angles, called vertical angles.

These opposite angles share a vertex. Furthermore, the most important point to bear in mind is that they are the same in measurement! This applies that regardless of where these straight lines cross, the angles converse each other will consistently share the exact value. These angles are called congruent angles.

Vertically opposite angles are congruent, so if you have a value for one angle, then it is feasible to find the others using proportions.

Proving the Theorem

Proving this theorem is somewhat easy. Primarily, let's pull a line and call it line l. Then, we will pull another line that intersects line l at some point. We will call this second line m.

After drawing these two lines, we will assume the angles formed by the intersecting lines l and m. To avoid confusion, we labeled pairs of vertically opposite angles. Therefore, we named angle A, angle B, angle C, and angle D as follows:

We understand that angles A and B are vertically opposite because they share the same vertex but don’t share a side. If you recall that vertically opposite angles are also congruent, meaning that angle A is identical angle B.

If we look at angles B and C, you will notice that they are not joined at their vertex but close to one another. They share a side and a vertex, meaning they are supplementary angles, so the total of both angles will be 180 degrees. This instance repeats itself with angles A and C so that we can summarize this in the following manner:

∠B+∠C=180 and ∠A+∠C=180

Since both sums up to equal the same, we can add these operations as follows:

∠A+∠C=∠B+∠C

By removing C on both sides of the equation, we will end with:

∠A=∠B

So, we can say that vertically opposite angles are congruent, as they have identical measure.

Vertically Opposite Angles

Now that we know the theorem and how to prove it, let's talk explicitly about vertically opposite angles.

Definition

As we stated, vertically opposite angles are two angles made by the intersection of two straight lines. These angles opposite one another fulfill the vertical angle theorem.

Still, vertically opposite angles are never adjacent. Adjacent angles are two angles that have a common side and a common vertex. Vertically opposite angles at no time share a side. When angles share a side, these adjacent angles could be complementary or supplementary.

In case of complementary angles, the addition of two adjacent angles will total 90°. Supplementary angles are adjacent angles whose addition will equal 180°, which we just used in our proof of the vertical angle theorem.

These concepts are appropriate within the vertical angle theorem and vertically opposite angles due to this reason supplementary and complementary angles do not satisfy the properties of vertically opposite angles.

There are various properties of vertically opposite angles. Still, odds are that you will only need these two to secure your exam.

  1. Vertically opposite angles are always congruent. Therefore, if angles A and B are vertically opposite, they will measure the same.

  2. Vertically opposite angles are never adjacent. They can share, at most, a vertex.

Where Can You Locate Opposite Angles in Real-Life Circumstances?

You might wonder where you can use these concepts in the real life, and you'd be amazed to observe that vertically opposite angles are very common! You can find them in many daily objects and circumstances.

For example, vertically opposite angles are formed when two straight lines overlap each other. Inside your room, the door installed to the door frame produces vertically opposite angles with the wall.

Open a pair of scissors to produce two intersecting lines and alter the size of the angles. Track junctions are also a great example of vertically opposite angles.

Eventually, vertically opposite angles are also discovered in nature. If you look at a tree, the vertically opposite angles are made by the trunk and the branches.

Be sure to observe your surroundings, as you will find an example next to you.

PuttingEverything Together

So, to sum up what we have discussed, vertically opposite angles are formed from two intersecting lines. The two angles that are not next to each other have the same measure.

The vertical angle theorem defines that in the event of two intersecting straight lines, the angles made are vertically opposite and congruent. This theorem can be tried out by drawing a straight line and another line intersecting it and applying the theorems of congruent angles to complete measures.

Congruent angles means two angles that measure the same.

When two angles share a side and a vertex, they cannot be vertically opposite. However, they are complementary if the sum of these angles totals 90°. If the sum of both angles equals 180°, they are assumed to be supplementary.

The total of adjacent angles is always 180°. Consequently, if angles B and C are adjacent angles, they will at all time equal 180°.

Vertically opposite angles are pretty common! You can discover them in many everyday objects and circumstances, such as paintings, doors, windows, and trees.

Further Study

Search for a vertically opposite angles worksheet online for examples and exercises to practice. Mathematics is not a onlooker sport; keep applying until these theorems are well-established in your brain.

However, there is nothing humiliating if you require additional support. If you're struggling to grasp vertical angles (or any other ideas of geometry), consider enrolling for a tutoring session with Grade Potential. One of our expert instructor can assist you grasp the material and nail your following examination.