Answer is :
can find it on
Since it is shown that 2 of the sides of the triangle are congruent, we can assume that they have the same angle measures.
so to solve for the missing angle you can set up an equation equal to 180 since all triangles add up to 180 degrees.
21 + 21 + x = 180
42 + x = 180
x = 138
the value of the missing angle should be 138 degrees
hope this helped
The measure of the unknown angle are; a) x = 89 degrees, b) p = 92 degrees.
<h3>What is the sum of all the angles of a regular polygon?</h3>
For a regular polygon of any number of sides, the sum of its exterior angle is 360°.
We already know that a 4-sided polygon's angles add up to 360 degrees.
So to find the value of x:
69 + 118 + 84 + x = 360
x = 360 - (69 + 118 + 84)
x = 89 degrees
b)
For a 4-sided polygon, we also know that the outside angles add up to 360 degrees.
So to find the value of p:
100 + 62 + 106 + p = 360
p = 360 - (100 + 62 + 106)
p = 92 degrees
Learn more about interior angles of a regular polygon here:
brainly.com/question/14173422
#SPJ1