Question
In the following, write the correct answer.
In $\triangle\text{ABC}$ if BC = AB and $\angle\text{B}=80^{\circ}$ then is equal to:
In $\triangle\text{ABC}$ if BC = AB and $\angle\text{B}=80^{\circ}$ then is equal to:
✓
Answer
- 50º
Solution: In $\triangle\text{ABC}$ we have BC = AB
But $\angle\text{B}=80^{\circ}$ $\angle\text{A}+\angle\text{B}+\angle\text{C}=180^{\circ}$
$=\angle\text{A}+80^{\circ}\angle\text{A}=180^{\circ}$ $=2\angle\text{A}=100^{\circ}$
$=\angle\text{A}=100^{\circ}\div2=50^{\circ}$
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