It's an isosceles triangle so angles A and BCA are congruent.
Angle BCA is the supplement of BCD, so 180-109 = 71.
Angle A is congruent to that, so A=71 degrees.
Let's see if we can get that in the format they want, kind of as a proof.
1. ∠BCD=109° Reason: Given
2. AB ≅ BC Reason: Given
3. ∠BCA = 71° Reason: Linear pairs are supplementary
4. ΔABC is isosceles. Reason: Definition of isosceles
5. ∠A ≅ ∠BCA Reason: Isoceles triangle theorem
6. ∠A = 71° Reason: Def congruent
Answer: 71 degrees
Answer:
14
Step-by-step explanation:
the diameter is the radius multiplied by 2
[1], [3] => a = 49,000/2 = 24,500 => b +c = 24,500 => c = 24,500 - b;
[2] => 25*24,500 + 20b + 15c = 1,052,000 => 20b + 15c = 1,027,500;
20b + 15*(24,500 - b) = 1,027,500 => 5b = 733,500 => b = 146,700 =>
c = - 122,200;
