Answer:
40.4
Explanation:
Triangle TUV is similar to triangle XYZ.
Notice the order in which TUV and XYZ are written.
Angles are corresponding to angles in the same position in the names.
<T corresponds to <X.
<U corresponds to <Y.
<V corresponds to <Z.
In similar triangles, corresponding angles are congruent.
<T is congruent to <X.
<U is congruent to <Y.
<V is congruent to <Z.
m<T = m<X = 63.1°
m<U = m<Y
m<V = m<Z = 76.5°
m<X + m<Y + m<Z = 180°
63.1° + m<Y + 76.5° = 180°
m<Y + 139.6° = 180°
m<Y = 40.4°