Bisector - Examples, Exercises and Solutions

Understanding Bisector

Complete explanation with examples

A bisector is a line segment that passes through the vertex of an angle and divides it into two equal angles.

The bisector can appear in a triangle, parallelogram, rhombus and in other geometric figures.

For example, a bisector that passes through an angle of 120° 120° degrees will create two angles of 60° 60° degrees each.

A1  -  Bisector

Detailed explanation

Practice Bisector

Test your knowledge with 7 quizzes

a is a bisector.

\( ∢BAC = 80° \)

Calculate angle \( \alpha \).

αααaaaAAABBBCCC

Examples with solutions for Bisector

Step-by-step solutions included
Exercise #1

Calculate angle α \alpha given that it is a bisector.

ααα606060AAAaaa

Step-by-Step Solution

Since an angle bisector divides the angle into two equal angles, and we are given that one angle is equal to 60 degrees. Angle α \alpha is also equal to 60 degrees

Answer:

60

Video Solution
Exercise #2

BD is a bisector.

What is the size of angle ABC?

656565AAABBBCCCDDD

Step-by-Step Solution

Since we are given that the value of angle DBC is 65 degrees, and we know that the angle bisector divides angle ABC into two equal angles, we can calculate the value of angle ABC:

65+65=130 65+65=130

Answer:

130

Video Solution
Exercise #3

Which of the following figures has a bisector?

Step-by-Step Solution

The answer is C because the angle bisector divides the angle into two equal angles. In diagram C, the angle bisector divides the right angle, which is equal to 90 degrees, into 2 angles that are equal to each other. 45=45 45=45

Answer:

4545

Video Solution
Exercise #4

ABCD is a square.

ABC=? ∢\text{ABC}=\text{?}

AAABBBDDDCCC

Step-by-Step Solution

Due to the fact that all angles in a square are equal to 90 degrees, and BC bisects an angle, we can calculate angle ABC accordingly:

90:2=45 90:2=45

Answer:

45

Video Solution
Exercise #5

ABCD is a deltoid.

DAC=? ∢DAC=\text{?}

AAABBBCCCDDD2x602x

Step-by-Step Solution

As we know that ABCD is a deltoid, and AC is the bisector of an angle and therefore:

BAC=CAD=2X BAC=CAD=2X

Now we focus on the triangle BAD and calculate the sum of the angles since we know that the sum of the angles in a triangle is 180 degrees:

2X+2X+2X+60=180 2X+2X+2X+60=180

6X+60=180 6X+60=180

18060=6X 180-60=6X

120=6X 120=6X

We divide the two sections by 6:1206=6x6 \frac{120}{6}=\frac{6x}{6}

20=x 20=x

Now we can calculate the angle DAC:

20×2=40 20\times2=40

Answer:

30

Video Solution

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