Question

find the value of the unknown interior angle X in each of the following diagrams ​

Answer 1

Answer:

(1) 180-115=65

65+50+x=180

×=180-115=65

(2)180--80=100

100+30+x=180

x=180-130=50

(3)180-70=110

110+36+x=180

x=180-146=34

Answer 2

We know, Sum of two interior opposite angles of triangle is equal to its exterior angle.

Now, Applying this theorem to each of the figure in the question, we get,

$1.) \bf \: \: x + 50 \degree = 115\degree \\ = > \bf \: \: \: \: \: x = 115\degree - 50\degree \\ = > \bf \: \: \: \: \: x = 65\degree$

$2.) \bf \: \: x + 30\degree = 80\degree \\ \bf = > \: \: \: \: x = 80\degree - 30\degree \\ \bf = > \: \: \: \: x = 50\degree$

$3.) \bf \: \: x + 36\degree = 70\degree \\ \bf = > \: \: \: \: \: \: x = (70 - 36)\degree \\ = > \bf \: \: \: \: \: \: x = 34\degree$