Question 1

What is a right triangle?

Accepted Answer

A right triangle is a triangle with one angle measuring exactly 90°. The side opposite that angle is called the hypotenuse, and it is always the longest side.

Question 2

How do you find the missing side of a right triangle?

Accepted Answer

If two sides are known, the Pythagorean theorem can be used:

a² + b² = c²

If an angle and a side are known, sine, cosine, or tangent can be used depending on the relationship between the known side and the angle.

Question 3

What is the Pythagorean theorem?

Accepted Answer

The Pythagorean theorem states that for a right triangle, the square of the hypotenuse equals the sum of the squares of the two legs:

a² + b² = c²

Question 4

How do you find the hypotenuse?

Accepted Answer

If the two legs are known, calculate:

c = √(a² + b²)

For example, legs of 6 and 8 produce a hypotenuse of 10.

Question 5

How do you find the missing angle?

Accepted Answer

Use an inverse trigonometric function based on the known sides:

sin⁻¹, cos⁻¹, or tan⁻¹

The appropriate function depends on which sides are known relative to the angle.

Question 6

What is SOH-CAH-TOA?

Accepted Answer

SOH-CAH-TOA is a memory aid for the three basic right-triangle trigonometric relationships:

SOH: sin = opposite / hypotenuse

CAH: cos = adjacent / hypotenuse

TOA: tan = opposite / adjacent

Question 7

Can I use this calculator with degrees and radians?

Accepted Answer

Yes. The calculator supports selecting the angle unit when working with angle-based calculations. Use degrees for values such as 30° or 45°, and radians for values such as π/6 or π/4.

Question 8

How do I know which side is the hypotenuse?

Accepted Answer

Find the 90° angle first. The side directly opposite that angle is the hypotenuse.

Question 9

Can a right triangle have two right angles?

Accepted Answer

No. The angles of a triangle add up to 180°. If one angle is already 90°, the other two must be acute angles whose measures add up to 90°.

Question 10

What is the area of a right triangle?

Accepted Answer

The area is:

Area = ½ × base × height

The base and height are the two perpendicular legs of the right triangle.

Question 11

What is the perimeter of a right triangle?

Accepted Answer

The perimeter is the sum of its three side lengths:

Perimeter = a + b + c

Question 12

Can the calculator solve a triangle from one side and one angle?

Accepted Answer

Yes, when the provided measurements are sufficient to determine the triangle. A right triangle already has one known 90° angle, so an appropriate side-and-angle combination can provide enough information to calculate the remaining measurements.

Right Triangle Calculator

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