Completing Proofs Involving Linear Pairs Given: m ZELG = 124°

Prove: x = 28

Statements

Reasons

1. m ZELG = 124

1. given

2. m ZELD = 2x

2. given

H

L

3. ZELG and ZELD are

a linear pair

3. definition of a linear pair

(2x)

G

4. m ZELD + m ZELG = 180

4.

Ε

• F.

5. 2x + 124 = 180

5. substitution

Complete the steps in the two-column proof.

6.

6. subtraction property

7. x = 28

7. division property

Intro

Done

vity

1: angle addition postulate

2: 2x=56

Step-by-step explanation:

a 4/6 = 9/12   not proportional

step-by-step explanation:

to find which are not proportional, we can use cross products

if it is true, they are proportional.   if it is not true, they are not proportional.

a 4/6 = 9/12

4* 12 = 6*9

48 = 54

not this is not proportional  

b 2/3 = 12/18  

2* 18 = 3 * 12

36 = 36

this is proportional

c 5/4 = 10/8  

5*8 = 4*10

40 = 40

this is proportional

d 7/5 = 35/25

7*25 = 5 * 35

175 = 175

is proportional