Answer:
50°
Step-by-step explanation:
I am assuming that the shape is a right triangle.
All interior angles of a triangle add up to 180°.

The missing angle should be 50°.
Hope this helps.
In order from least to greatest is 8.7, 8.83, 26/3, 79
Hope this helps you and good-luck
The proof is given below. Please go through it.
Step-by-step explanation:
To solve Δ ABC ≅ Δ DBC
From Δ ABC and Δ DBC
AB = BD (given)
AC = CD (given)
BC is common side
By SSS condition Δ ABC ≅ Δ DBC ( proved)
To solve Δ EHF ≅ Δ GHF
Δ EHF and Δ GHF
EH = HG ( given)
∠ EFH = ∠ GFH ( each angle is 90°)
HF is common side
By RHS condition
Δ EHF ≅ Δ GHF