Respuesta :

5. If the sum of all the angles of a triangle is 180°

In an isosceles triangle two of the angles are equal. Let us call one of these angles x

Therefore, 2 x + 120° = 180°

2 x = 60°

x = 60° / 2

x = 30°

Therefore, The measure of the base angle is 30°.

6. The base angles of an isosceles triangle are equal

So, (7 x + 5)° = (x + 47)°

7 x - x = 47 - 5

6 x = 42

x = 7

Therefore, the value of x is 7