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Answer:
<DEB= 125 degrees
Step-by-step explanation:
To get this, you would need to know all 2 angles of the triangle.
To find the first angle, simply do 180-107 to get 73(because supplementary angles add up to 180 degrees).
Next, 180-52(given angle)-73 to get 55 because the 3 angles of a triangle add up to 180(triangle angle sum theory).
You would see that <DEB is part of another supplementary angle so, do 180-55 to get 125.
<DEB=125 degrees.
Answer:
125 is the answer.
Step-by-step explanation:
Let's calculate all the internal angles in the triangle 1st.
∠ACE + ∠ECB =180
107 +∠ECB =180
∠ECB =73
The sum of internal angles in a triangle is 180 so
∠ECB +∠EBC +∠CEB =180
73+52+∠CEB=180
∠CEB=180-125
∠CEB = 55
Since CB is a line
∠CEB +∠DEB =180
55+∠DEB =180
∠DEB=125