In an isosceles triangle, the vertex angle is twice the each base angle. What is the vertex angle?

2 Answers
Nov 14, 2015

#90^@#

Explanation:

Since the sum of the interior angles of any triangle adds up to #180^@# and also the base angles of an isosceles triangle are equal,we may let the base angles be #x#, then the vertex angle is #2x#.
#therefore x+x+2x=180^@#.
#therefore x=45^@#.
Therefore the vertex angle is #90^@#.

Jan 9, 2018

#90^circ#

Explanation:

An isosceles triangle has two sides of equal length. Likewise, the opposite angles of the sides are the same

So lets assume each angle be #x# and the bigger angle be #2x# (since it is twice the base angle)

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Now, we know that sum of the angles in a triangle is 180 degree

So,

#rarr2x+x+x=180^circ#

#rarr4x=180^circ#

#rarrx=180/4#

#color(green)(rArrx=45^circ#

Now the other angle is #2x# which is #45xx2=90^circ#

Hope this helps!!! ☺☻ have a good day...