In this problem
we have an isosceles triangle
because
BU=UG ------> given
that means
m by definition of isosceles triangle
so
Remember that
In any triangle, the sum of the interior angles must be equal to 180 degrees
therefore
substitute given values
3x+2(x+10)=180
solve for x
3x+2x+20=180
5x=180-20
5x=160
x=32
therefore