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Because these are congruent triangles, each individual part of the triangles are congruent too. This means that <C is congruent to <Z, so <Z= 35 degrees. <A is congruent to <X, so <A = 65 degrees. Now to find angle Y, we know that all angles in a triangles add up to 180 degrees. So, if we add together <X , <Z, and <Y, they equal 180.
<X + <Y + <Z = 180 now fill in what we know.
65 + y + 35 =180
100 + y = 180
y= 80 so, m<Y =80 degrees.
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