Answer:
A. Angles 7 and 8 are vertical angles, hence congruent.
B. The angles marked with y-expressions are vertical angles, hence congruent. This can be used to solve for y by equating the expressions.
C. y = 24; ∠7 = ∠8 = 89°
Explanation:
A.
Angles 7 and 8 are vertical angles, hence congruent.
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B.
The angles marked with y-expressions are vertical angles, hence congruent. This relationship can be used to solve for y by equating the expressions.
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C.
5y -29 = 3y +19
2y = 48 . . . . . . . . . . add 29-3y
y = 24
Then angles 7 and 8 are ...
∠7 = ∠8 = 180° -(5y-29)° = 209° -5(24)°
∠7 = ∠8 = 89°