Question

Meg described four triangles as shown below:

Triangle P: All sides have length 7 cm.
Triangle Q: Two angles measure 55°.
Triangle R: Two sides have length 8 cm, and the included angle measures 60°.
Triangle S: Base has length 8 cm, and base angles measure 55°.

Which triangle is not a unique triangle?

Triangle P
Triangle Q
Triangle R
Triangle S

Answer 1

@Kacchan

Answer 2

@jimthompson5910 is b correct for this?

Answer 3

Choice B is correct

The fact that we know that 2 angles are 55 degrees isn't enough to set up a single unique triangle.

For instance, we could scale to enlarge the triangle, and keep the angles the same like so

We would need to know some info about the side length(s) to be able to form a unique triangle.

Answer 4

Anyways, I believe that triangle P because Notice how all interior angles and sides are equal

Answer 5

@jimthompson5910 Does triangle p make sense?

Answer 6

would it be a?

Answer 7

Triangle P is unique. We can rotate, shift, and reflect it, but that wouldn't change the triangle at all in terms of size and shape.

Answer 8

True

Answer 9

Triangle Q on the other hand, we can enlarge or reduce the triangle while keeping the same angles. This triangle isn't unique. Infinitely many triangles are possible if all we know is that 2 angles are 55 degrees.

Answer 10

Alright, i finally understand