Step-by-step explanation:
A) no because 60+80+80=220° and in a triangle the sum of the angles must be equal to 180°
B) yes: sum of any two sides of a triangle is greater than the third side and difference between two sides is less than third side. So
(4+5) > 6 (5+6) > 4 (4+6) > 5
(5-4) < 6 (6-5) < 4 (6-4) < 5
C) no: sum of any two sides of a triangle is greater than the third side and difference between two sides is less than third side. So
(4+5) < 15
D) yes (just do the drawing test)
E) yes (just do the drawing test)
