5°
As you have written quadrilateral abcd is a parallelogram if it's opposite angles are congruent.
So we have to find the measure of opposite pair of angles.
I have drawn four parallelograms
A) 95°, 85°
∠a+ ∠b=180°
∠a = ∠c =95°
∠b = ∠d =85°
2. b) 105°, 75°
∠a = ∠c =105°
∠b = ∠d =75°
c). 115°, 65°
∠a = ∠c =115°
∠b = ∠d =65°
D) 125°,55°
∠a = ∠c =125°
∠b = ∠d =55°
In all the four cases
∠a+ ∠b=180°
∠b + ∠c=180°
∠c + ∠d =180°
∠d + ∠a=180°
and in all cases ∠a=∠c , ∠b=∠d
as sum of interior angles on same side of transversal is 180° so opposite sides become parallel.If in a quadrilateral opposite sides are parallel then it is a parallelogram.
So we can say that quadrilateral abcd is a parallelogram.
Answer:
The measure of the quadrilateral depends...
Parallelogram = B. 65 degrees
Trapezoid = C. 115 degrees
