Steply

Can 14, 9 and 6 make a triangle

Step by step, with the reason for every step · Can it make a triangle · Geometry

Step by step

The question

Question: can sides of 14, 9 and 6 make a triangle?

sides 14, 9, 6

For a triangle, the two short sides together must be longer than the longest side.

Else they cannot meet.

the two short sides must reach
round the longest one

1 Add the two short sides

The longest side is 14.

We lay it down first.

The two short sides are 6 and 9.

Together: 15.

= 6 + 9 = 15

2 Compare with the longest

Swing them up from the ends.

15 is more than 14, so they meet at the top.

So yes: they make a triangle.

= 15 > 14 → yes, a triangle

3 Check

Let's check the other two pairs: 6 plus 14 is 20, and 9 plus 14 is 23.

Both are more than the third side.

So only the short pair decides.

So the answer is right!

6 + 14 = 20 > 9, 9 + 14 = 23 > 6

Let's look back.

First: add the two short sides.

Then: compare with the longest.

Last: check.

Answer
= 15 > 14 → yes, a triangle

Your turn

Try this one yourself, then check:

sides 10, 8, 3
Show the answer
yes

More from Can it make a triangle

The whole lesson: Can it make a triangle →