Given: MZADE = 60° and m2CDF = (3x + 15) Prove: x = 15
(3x + 15)
60° D
What is the missing statement and the missing reason in
step 5?
Statements
Reasons
1 MZADE -60°
1. given
mZCDF - (3x+15)
2. ZADE and ZCDF are vert. ZS 2. def. of vert. Zs
3. ZADE a CDF
3. vert. ZS
4. MZADE - mZCDF
4. def. of a
5 ?
5. ?
6. 45 - 3x
6. subtr. prop
7. 15 = x
7. div. prop
Statement: 60 3x + 15; Reason: substitution
Statement: x = 15; Reason: subtraction property of
equality
Statement: 60 = 3x + 15: Reason: transitive property
Statement: x = 15; Reason: subtraction and division
properties of equality