Question

If one of the angles of a triangle is 120ᵒ and the triangle is isosceles, then half of sum of angles of the other two angles can be

Answer 1

Answer:

60

Step-by-step explanation:

$let \: the \: other \: angles \: be \: x \: degree \: each \\ \\ then \: \: x + x + 120 = 180 \: \: \: \: by \: angle \: sum \: property \\ \\ 2x = 60 \\ \\ x = 60 \\ \\ then \: \: \: \: \frac{1}{2}(x + x) = x = 60 \: \: (answer).$

Answer 2

Given,

$\[\angle A = 120^\circ \]$

Isosceles triangle

Solution,

Isosceles triangle has two sides of equal length. So its two angles will also be equal.

Sum of angles of triangle is $\[180\]$°

Consider the angles are A, B, C.

$\[\begin{array}{l}\angle A + \angle B + \angle C = 180^\circ \\ \Rightarrow 120^\circ + \angle B + \angle C = 180^\circ \\ \Rightarrow \angle B + \angle C = 60^\circ \end{array}\]$

Sum of other two angles of triangle $\[ = 60^\circ \]$

Half of the sum of other two angles of triangle,

$\[\begin{array}{l} = \frac{{60^\circ }}{2}\\ = 30^\circ \end{array}\]$

Hence the half of the sum of other two angles of triangle is $\[30^\circ \]$