Alfa, Beta and Gamma are inner angles in a triangle

Alfa, Beta and Gamma are inner angles in a triangle. If Alfa = Beta + Gamma, what can’t be the size of Beta?

(a) 44 degrees.
(b) 45 degrees.
(c) 89 degrees.
(d) 90 degrees.
(e) There isn’t enough data to determine.

The best answer is D.
If Beta is 90 degrees than Alfa is bigger than 90 and the sum of the angles in the triangle will be bigger than 180 degrees.



In a triangle, one side is 6 Cm and another side is 9 Cm. which of the following can be the perimeter of the triangle?

(a) 18.
(b) 25.
(c) 30.
(d) 32.
(e) 34.

The best answer is B.
The third side of the triangle is larger than 3 (The difference between the other two) and smaller than 15 ( The sum of the other two).
The perimeter is between (6+9+3 = 18) and (6+9+15 = 30). The only answer that is in this range is B.