Question

Find the value of x.
Please answer fast. First correct answer gets marked as brainliest. ​

Answer 1

Let the triangle be △ABC

Here we need to find angle A.

$\setlength{\unitlength}{1cm} \begin{picture}(6,2) \put(0,0){\vector(1,0){4}}\put(0,0){\line(1,3){1}}\put(2,0){\line(-1,3){1}}\qbezier(0.6,2)(0.9,1.5)(1.3,2)\put(1,1.5){ \bf x }\qbezier(1.8,0.6)(2.4,1.)(2.5,0)\put(1,1.5){ \bf x }\put(2,1){ \bf 130{\circ} }\put(-0.2,-0.25){ \bf B }\put(1.7,-0.25){ \bf C }\put(1,2.9){ \bf A }\put(4,-0.25){ \bf D }\end{picture}$

We have to find the two angles in the base to find the angle on the top.

So the exterior angle is 130° at the base. Since a line is 180° the interior angle (the angle in the triangle) would be ⇒ $\sf 180\° -130\°$

∴ One of the angles is 50°.

Since this is an isosceles triangle, two angles will be the same. Here two angles are 50°.

To find 'x' we need to know one thing.

All the angles of a triangle sum up to 180°.

So if two angles are 50° each then we need to solve the following equation⇒ $\sf 50+50+x=180$

$\sf 50+50+x=180$

$\sf 100+x=180$

$\sf x = 180-100$

$\sf x=80$

∴ $\sf \bf x=80\°$