Given: m zade = 60° and m 2cdf = (3x + 15)
prove: x = 15
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 - cdf
3. vert. zs
4. mzade = m2cdf
4. def. of
5. ?
15. ?
6. 45 - 3x
| 6. subtr. prop.
7. 15-x
| 7 div. prop
(3x + 15)
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