Triangle Congruent To Mirror Image?

Question

There's this one problem on the textbook that I don't understand...Thanks!
Suppose a given triangle is directly congruent to its mirror image. We can be sure that this triangle is? 1. Equilateral 2. Isosceles 3. Acute 4. Obtuse. And could u plz explain the answer too? Thanks!

Answer 1

Mirror image in this case means if you draw a line beside the triangle and flop it over (like the line was a mirror).
Congruent means identical. Now it should be kind of obvious that an Equilateral triangle (60,60,60) is going to be the same no matter how it is rotated or flipped. But an equilateral is also isosceles so will other isosceles triangles flip - yes because the they are symmetrical - equal sides and equal angles. What about acute? Nope - a 3,4,5 triangle is acute, but flipped over it is not congruent.
So we can be sure it is isosceles and it may be equilateral.

Answer 2

Image Of Isosceles Triangle

Answer 3

Congruent just means symmetrical, or all the sides when superimposed will match up.

So while the post above me says isosceles, this would only be true if the triangle was on it's "base", but if the triangle was laying down, it would no longer be congruent to the mirror image. So the only thing we *know* it is, is an equilateral.

Answer 4

If its directly congruent to its mirror image, then the triangle looks the same whether it is reversed or not. That means that there is at least one axis is symmetry, which means that the triangle must be isosceles (where the axis of symmetry is generally vertical through the middle).

Answer 5

Equilateral

Answer 6

Basically, if you can draw a line across the middle of the triangle and flip it or fold it upon itself, does it match up?

If it does, what can we say is true about the triangle?

(It's atleast isoscoles and might be equilateral)

Answer 7

it is in ordinary terms genuine if it relatively mentioned 2 ideal triangles that incorporate congruent nonright angles are comparable. you in ordinary terms want 2 pairs of corresponding angles to be congruent, and you quickly have one pair in case you be attentive to they are ideal triangles (the main suitable angles).