Answer:
No. There can be an obtuse angle or a right-angle in an isosceles triangle.
Step-by-step explanation:
Explanation:
No. You can three types of isosceles triangles:
acute-angled isosceles triangle
All the angles are acute and the base angles are equal.
eg:
75
°
,
75
°
,
30
°
or
50
°
,
50
°
,
80
°
right-angled isosceles triangle
One angle is 90
° and the other two are both 45
°
45
°
,
45
°
,
90
°
←
(like one of the usual set squares)
obtuse-angles isosceles triangle
One angle is obtuse and the base angles are equal.
eg:
30
°
,
30
°
,
120
°
or
25
°
,
25
°
,
130
°
Ofcourse there can only be one 90
°
or
one obtuse angle in a triangle. The other two angles MUST be acute, else the sum would be more than 180
°