Triangle STU has reflected over line m to form Triangle S'T'U'. What is the value of y?
A. 2
B. 6
C. 3
D. 5
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Answer:
D. 5
Step-by-step explanation:
The congruence of S'T' with ST tells you ...
9 = x +7
2 = x
The congruence of S'U' and SU tells you ...
4x = y +3
4·2 -3 = y = 5 . . . . substitute the value of x; subtract 3