Write the letter of the property, definition, or postulate that justifies each statement.
11. If m/ABC = 90°, then ZABC is a right angle.
12. If m23+ m24 = 180°, then 23 and 24 are
supplementary angles.
13. If m/PQR = m/RST, then ZPQR = ZRST
14. If 21 and 22 form a right angle, then 21 and 22
are complementary angles.
15. If ZX and Y are supplementary and ZX and Z
are supplementary, then 2Y = LZ
16. If ZJ and ZK are vertical angles, then ZJ = ZK
A. Definition of Congruence
B. Definition of Angle Bisector
C. Definition of Complementary Z's
D. Definition of Supplementary Z's
E. Definition of Perpendicular
F. Definition of a Right Angle
G. Angle Addition Postulate
H. Vertical Angles Theorem
I. Complement Theorem
J. Linear Pair (Supplement) Theorem
K. Congruent Complements Theorem
L. Congruent Supplements Theorem
17. If ZPQR and ZSTU are complementary angles, then mZPQR+ m2STU = 90°.
18. If 25 and 26 form a linear, then 25 and 26 are supplementary angles.