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Classify a triangle with sides 6, 9, 6

Step by step, with the reason for every step · Classifying angles and triangles · Geometry

Step by step

The question

Question: find what kind of triangle has sides 6, 9, 6.

1 Compare the sides

There are three names, from how many sides are equal.

Two sides are 6.

They are equal.

6 = 6

The third side, 9, is different.

6 ≠ 9

Marks show the equal sides.

Careful!

Two equal sides is enough for isosceles.

Careful: isosceles: 2 equal sides

2 Name it

So the triangle is isosceles.

triangle is isosceles

3 Check

Let's check: count the equal sides on the picture: 2.

That is isosceles.

equal sides: 2 → isosceles

Let's look back.

First: compare the sides.

Then: name it.

Last: check.

Answer
triangle is isosceles

Your turn

Try this one yourself, then check:

What kind, by its sides?
Show the answer
isosceles

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