Remember that the interior angles of a triangle add up to 180º.
A right-angled triangle has one 90º angle.
An isosceles triangle has two equal angles.
An equilateral triangle has three equal angles, each of size 60º
A scalene triangle has no equal angles.
Two of the angles in a triangle are 35º and 110º. Which type of triangle is it?
We must first work out the third angle which will be:
180º - (35º + 110º) = 180º - 145º = 35º
So the triangle has angles 35º , 110º, 35º
Two angles are equal, so it is isosceles.
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