Answer: x = 36
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Explanation:
Focus on triangle TUS. The inner angles here are:
Note how the angle measure for S is the supplement of 2x, which is adjacent to the angle S we have.
Add up those three angles and set the sum equal to 180
T+U+S = 180
y+x+180-2x = 180
y-x = 180-180
y-x = 0
y = x
We'll use this later.
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The diagram shows that angle VTU = y+y = 2y.
Focus your attention on triangle TUV.
Since TU = UV, this means the base angles T and V (which are opposite the congruent sides) are congruent angles. We found that angle T was 2y earlier. This means angle V is also 2y.
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Now shift your focus to triangle TSV.
This triangle has the inner angles
Recall earlier that we found y = x at the conclusion of the first section. Using that and the fact that the angles of triangle TSV add to 180, we get...
T+S+V = 180
2x+y+2y = 180
2x+3y = 180
2x+3x = 180 .... replace y with x, since y = x
5x = 180
x = 180/5
x = 36
This is the value of y as well.
