### Grade9: Lesson 5-8 Special right triangles

Recognizing special right triangles in geometry can help you to answer some questions quicker.

There are two types of special right triangles and they have the following properties:

**45 ^{°}-45^{°}-90^{°} triangle**

In this triangle, the important thing to remember is that the legs have equal length.

Formula: **Hypotenuse** = **√(2)**×(Leg)

**30 ^{°}-60^{°}-90^{°} triangle**

Formulas

**Long Leg** = (√3) × (**Short Leg**)

**Hypotenuse** = 2. **short leg**

*You can also use the Pythagorean theorem, but if you can see that it is a special triangle it can save you some calculations.*

**What follows is a PowerPoint presentation that will help you understand the content of the lesson in a better and easier way**, (*pps*).