Question

A triangle has side lengths of 12 cm, 15 cm, and 20 cm. Classify it as acute, obtuse, or right. (1 point)

acute
obtuse
right
There is not enough information.

Answer 1

I wanna choose Right...

Answer 2

By the converse of the Pythagorean Theorem,
if 20^2 = 15^2 + 12^2, then "right" is correct.

Check the arithmetic and let us know.
@zhane2015

Answer 3

What is 20*20?

Answer 4

400

Answer 5

Good. What is 15 times 15?

Answer 6

You can enter "15 times 15" in the Google search box and get the product. @zhane2015

Answer 7

> I wanna choose Right... @zhane2015 Suggest you not choose until the arithmetic is done.

Answer 8

225

Answer 9

Okay.

I'll do 12 times 12 to get 144.

Answer 10

12 cm, 15 cm, and 20 cm.
------------------------

Question: Is 12^2 + 15^2 = 20^2
That is, is 144 + 225 = 400?
Yes or No?

Answer 11

no

Answer 12

Okay. Therefore, the triangle is NOT Right.
That leaves Obtuse and Acute.

Check out this attachment below:

(comes from http://jwilson.coe.uga.edu/emt668/emat6680.folders/brooks/6690stuff/righttriangle/pythagconv.html )

Answer 13

OMG you're the Best!

Answer 14

Let's test for acute.

Is 400 < 225 + 144 [ Is 20^2 < 12^2 +15^2 ]

Yes or No? @zhane2015

Answer 15

no

Answer 16

So it's obtuse

Answer 17

Correct.

Answer 18

Thank You so much I really appreciate it

Answer 19

Glad to help. Learn that theorem on the chart and you'll get all this type problem correct.