Question

Each of the base angle of an isosceles triangle is twice the vertical angle then the vertical angle is

• A. ${35}^{\circ }$
• B. ${36}^{\circ }$
• C. ${37}^{\circ }$
• D. ${38}^{\circ }$

Answer 1

The correct option is B ${36}^{\circ }$

Let the vertical angle be x

Then each base angle = 2x
Remember that sum of the 3 angles of the triangle = 180
i.e. $2x+2x+x=180$

$\Rightarrow 5x+{180}^0$

$\Rightarrow x={36}^0$

Then vertical angle is ${36}^0$