Special Right Triangles

Front

What is a 45°-45°-90° triangle?

Back

A special right triangle where the two legs are equal in length, and the angles are 45°, 45°, and 90°. The relationship between the lengths of the legs (x) and the hypotenuse (h) is h = x√2.

Tags

CCSS.8.G.B.8

Front

What is a 30°-60°-90° triangle?

Back

A special right triangle where the angles are 30°, 60°, and 90°. The relationship between the lengths of the shorter leg (x), the longer leg (y), and the hypotenuse (h) is y = x√3 and h = 2x.

Tags

CCSS.HSG.CO.C.10

Front

What is the Triangle Inequality Theorem?

Back

The sum of the lengths of any two sides of a triangle must be greater than the length of the third side.

Front

Can a triangle have side lengths of 4, 6, and 15?

Back

No, because 4 + 6 is not greater than 15, violating the Triangle Inequality Theorem.

Front

What is an acute triangle?

Back

A triangle where all three angles are less than 90°.

Tags

CCSS.4.G.A.2

Front

What is an obtuse triangle?

Back

A triangle that has one angle greater than 90°.

Tags

CCSS.4.G.A.2

Front

What is a right triangle?

Back

A triangle that has one angle equal to 90°.

Tags

CCSS.4.G.A.2

Front

What is an equilateral triangle?

Back

A triangle where all three sides are equal in length and all angles are 60°.

Tags

CCSS.4.G.A.2

Front

What is an isosceles triangle?

Back

A triangle that has at least two sides of equal length and the angles opposite those sides are equal.

Tags

CCSS.4.G.A.2

Front

What is the formula for the area of a triangle?

Back

Area = 1/2 * base * height.

Tags

CCSS.6.G.A.1