Isosceles Triangles

Front

What is an isosceles triangle?

Back

An isosceles triangle is a triangle that has at least two sides of equal length.

Front

What is the property of angles in an isosceles triangle?

Back

In an isosceles triangle, the angles opposite the equal sides are also equal.

Front

Back

Front

How do you find the height of an isosceles triangle?

Back

The height can be found by drawing a perpendicular line from the vertex opposite the base to the midpoint of the base.

Front

What is the formula for the area of an isosceles triangle?

Back

Front

If the base of an isosceles triangle is 10 cm and the height is 8 cm, what is the area?

Back

Front

What is the relationship between the sides of an isosceles triangle and its angles?

Back

The larger the angle, the longer the side opposite to it; conversely, the smaller the angle, the shorter the side.

Front

What is the base of an isosceles triangle?

Back

The base is the side that is not equal in length to the other two sides.

Front

In an isosceles triangle, if one angle measures 40 degrees, what are the measures of the other two angles?

Back

The other two angles will each measure 70 degrees, since the sum of angles in a triangle is 180 degrees.

Front

What is the congruence postulate that applies to isosceles triangles?

Back

The Side-Angle-Side (SAS) postulate can be used to prove that two isosceles triangles are congruent.