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[maiden breach]

whats the question

[vestal sundial]

180=3x+9x=12x -> x=180/12=15. Then using the information that the sum of triangles angles is 180 degrees we get equation 3x+45+y=180 -> 3*15+45+y=180 -> 90+y=180 ->=y=90

[hushed grove]

Considering that 9x and 3x are suplementary angles (their measures add 180 degrees), we can conclude that 9x + 3x = 12 x = 180.

So, x = 180/12
x = 15 degrees.

Furthermore, the triangle ABC is isoceles because the sides AC and AB have the same lenght.

One of the properties of the isoceles triangles are that their base angles measure the same, so if ∠ACB = 3x, than ∠ABC equals 3x too.

Considering the property of triangles that the sum of intern angles equals 180 degrees, so than we can determine the y angle.

3x + 3x + y = 180
3.15 + 3.15 + y = 180
45 + 45 + y = 180
90 + y = 180
y = 90 degrees.

[fleet vale]

thanks 🙂

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