Question

write a two - column proof. given: m∠gfi = 127°. prove: m∠efi = 40°. statements reasons 1. m∠gfi = 127° 1. given 2. m∠gfe + m∠efi = m∠gfi 2. angle addition postulate 3. m∠gfe + m∠efi = 127° 3. substitution property. (steps 1, 2) 4. m∠gfe=(9x - 3)°, m∠efi = 4x° 4. given 5. 9x - 3+4x = 127 5. substitution property 6. 13x - 3 = 127 6. combine like terms. 7. x = 7. addition property of equality

Explanation:

Step1: Add 3 to both sides

$13x - 3+3=127 + 3$

Step2: Simplify both sides

$13x=130$

Step3: Divide both sides by 13

$x = \frac{130}{13}=10$

Answer:

In statement 7, the first box is $13$ and the second box is $10$