Answer:
84°
Explanation:
Using the definition of an isosceles triangle given two congruent sides, two angles must be congruent/have the same measure. And using the triangle angle theorem, all must add up 180°. Let's say that the congruent angles are called a. And the two opposite angles sum up to 132° using the exterior angle theorem. Then the following system can be represented by:
2a + x = 180
a + x = 132
All you have to do is simply subtract them.
2a + x = 180
– a + x = 132
a = 48°
Now all we have to do is use the a + x = 132 equation.
And (Substitute) →
48° + x = 132°
–48° –48°
✓ x = 84°
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You could also use the definition of a straight angle, along with an isosceles triangle because of the two congruent angles so that:
180° – (132°) = 48°
and
180° – (48° + 48°) = 84°