Question 246890: how do you know if a triangle is scalene, equilateral, or right? thanks! =] Found 3 solutions by checkley77, richwmiller, solver91311:Answer by checkley77(12844) (Show Source):
You can put this solution on YOUR website! You have to know something about its sides or angles.
if all angles are the same or all sides are equal then it is equilateral.
if two angles or two sides are equal then it is isosceles
Sometimes you aren't told directly what it is.
If it has 3 equal sides it is equilateral. That's what equilateral means: equi- means equal and lateral means sides -- from the Latin. An equilateral triangle is also equiangular.
If it has 2 equal sides and the third side is different, it is an isosceles triangle. The Greeks called this equal legged is + skelos. An isosceles triangle also has two equal angles.
If it has all three sides different, it is scalene. Greek skalenos meaning uneven. A scalene triangle has angles of three different measures.
If one of the angles in the triangle is a right angle, that is it measures 90°, then it is a right triangle. Note, a right triangle can be either isosceles (in the specific case of a 45°-45°-90° triangle) or scalene (in the case of every other right triangle). A right triangle cannot be equilateral.
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