Given: m< ade = 60° and m< cdf = (3x + 15)°
prove: x = 15
what is the missing statement and the missing reason in
step 5?
reasons
· given
u
statements
1. mzade - 600
m2cdf - (3x+15)
2. zade and cdf are vert. zs
3. zade = cdf
4. mzade = m cdf
5 7
6. 45 - 3x
7. 15-x
3
(3x +15)
2. def. of vert. zs
vert. zsa
4. def. of a
5. ?
6. subtr. prop
7. div. prop
60°
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