Question

Can someone please explain step by step every detail on how to solve this and why ? thank you

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Answer 1

B) 100

Explanation:

The sum of the interior angles of a triangle add up to 180°. The small triangle on the top has two known angles: 70 and 30. If you add that together, you get 100, that means that the top angle must be 80 because 70 + 30 + 80 = 180.

Now look at the large triangle, the sum of the interior angles must add up to 180. We know that the top angle of the triangle is 80. We just figured that out. Then a + b must be 100, because 80 + 100 = 180.

Helping in the name of Jesus.

Answer 2

Answer: The sum of 3 angles in a triangle always is 180º, the answer is B

Explanation:

You see, the small triangle?

The sum of 3 angles is 180º, and we know 2 angles is 70º and 30º, so the left angle is equal to 180º-70º-30º=80º

Now, you look at the biggest triangle we have.

We have the top angle, is 80º that we found before, so a+b=180º-80º=100º