Isosceles triangle

An isosceles triangle has an angle against the base that measures 55°.
What is the size of the angle at the base of an isosceles triangle? (Calculation and procedure)

Your answer:

Help us improve! If you spot a mistake, please let let us know. Thank you!

Tips for related online calculators

Calculation of an isosceles triangle.
See also our trigonometric triangle calculator.

You need to know the following knowledge to solve this word math problem:

algebra

rearrange variables

planimetry

triangle

Units of physical quantities

angle

Grade of the word problem

practice for 12 year olds
practice for 13 year olds

We encourage you to watch this tutorial video on this math problem: video1

Related math problems and questions:

Triangle base angle
An isosceles triangle has an angle of 78°20' at the base. Calculate the size of the angle between the arms.
Isosceles triangle angles
The angle at the base of an isosceles triangle is 18 ° larger than the angle at the central vertex. Calculate the size of the interior angles.
Main/central vertex
ABC is an isosceles triangle with base BC and central vertex A. The angle at vertex A is 18°. What will be the size of the angle at vertex B?
Isosceles triangle angles
Determine the size of the interior angles in an isosceles triangle if you know that the angle opposite the base is 15° greater than the angles at the base.
Triangle angle calculation
In an isosceles triangle, the angle at the primary vertex is 20 ° smaller than twice the magnitude of the angle at the base. What are the interior angles of a triangle?
Triangle construction progress
An isosceles triangle ABY has a base AB of length 5 cm and an angle at the primary vertex of 50°. Write down the construction progress.
Flowerbed
The flowerbed has the shape of an obtuse isosceles triangle. The arm has a size of 7.6 meters, and an angle opposite the base size is 124°. What is the distance from the base to the opposite vertex?