Look at the isosceles right-angled triangle below.
Calculate its angles.
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Look at the isosceles right-angled triangle below.
Calculate its angles.
Let's remember that the sum of angles in a triangle is equal to 180 degrees.
In a right-angled triangle, there is one right angle equal to 90 degrees.
In an isosceles triangle, the base angles are equal to each other.
Therefore, we can calculate this in the following way:
In other words, the angle values in this triangle are 90, 45, and 45.
90, 45, 45
In a right triangle, the side opposite the right angle is called....?
The two base angles are equal! Since one angle is 90°, the other two must be equal to each other. They're the angles opposite the equal sides.
After subtracting the right angle (90°) from 180°, you get 90°. Since the two base angles are equal, divide: for each angle.
Look for the right angle symbol (small square) in the triangle diagram. This marks the 90° angle. The other two angles are across from the equal sides.
Yes! The process is the same:
That's fine! Not all triangles have nice whole number angles. Just make sure your three angles still add up to exactly 180°.
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