A triangle's interior angles will always add up to 180 degrees.
When one interior angle gets larger, the other angles must decrease in size.
If you attempt to make a triangle with two obtuse angles, you will find you can't do it in three lines. But you need an extra line in order to close the shape. But it won't be a triangle.
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:
55.1%
Step-by-step explanation:
When a number is a percent, then one mutliplies it by 100, because a percent is a way of representing a value out of 100. Therefore, 0.551 as a percent is;
0.551 * 100
55.1%
I'm confused what are you suppose to do