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Triangle ABC

maps to triangle XYZ

by a rotation of 90∘

counterclockwise about the origin followed by a reflection across the line y=x.

In triangle ABC,

m∠A=45∘,

m∠B=55∘,

and m∠C=80∘.

What is the measure of ∠Y?


i have tried 350, 76, 35,14, and none of them have been right

1 Answer

4 votes

Answer:

Hopes this helps

Explanation:

Therefore , the solution of the given problem of triangle comes out to be the angle Y has a value of roughly 76.4 degrees.

What precisely is a triangle?

Because a triangle has four or more extra parts, it is a polygon. Its form is a straightforward rectangle. A triangle is a rectangle with the edges A, B, and C. A singular plane but instead cube are produced by Euclidean geometry when the sides aren't truly collinear. A triangular is a shape if it has three sides and three angles. Angles are the points where a quadrilateral three sides meet. A triangle's sides add up to 180 degrees.

Here,

We can determine the images of locations A, B, and C using the following method:

=> A': (-yA, xA)

=> B': (-yB, xB)

=> C": (-yC', xC')

where C' is the rotated version of location C.

We can determine the side lengths of triangular ABC using the Law of Cosines:

Assume that

=> a = BC = 2R sin(A/2) = 2R sin(45/2) 1.441R,

=> b = AC = 2R sin(B/2) = 2R sin(55/2) 1.663R, and

=> c = AB = 2R sin(C/2) = 2R sin(80/2) 2.219R.

where R represents the triangular ABC's circumradius.

Now, by turning point C 90 degrees anticlockwise with respect to the origin, we can determine the coordinates of point C':

xC' = -yC

yC' = xC

Then, to obtain the picture of point C, we can reflect point C' across the line y = x:

xC"=yC' and yC"=xC'

Again employing the Law of Cosines, we can determine the triangular XYZ's side lengths:

=> x = YZ = 2R sin(A'/2) = 2R sin(35) ≈ 1.189R

=> y = XZ = 2R sin(B'/2) = 2R sin(45) ≈ 1.414R

=> z = XY = 2R sin(C'/2) = 2R sin(55) ≈ 1.630R

where the picture angles of angles A, B, and C are A', B', and C', respectively.

Last but not least, we can apply the Law of Cosines once more to determine the size of angle Y:

cos(Y) i= t (x2 + z2 - y2)/ (2xz)

cos(Y) = 0.224 Y = 76.4 °

As a result, the angle Y has a value of roughly 76.4 degree

User Sheka
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