Answer:
6.
- x = 15
- m∠CDF = 59°
- m∠FDE = 73°
- m∠CDE = 132°
7.
Explanation:
Question no. 6:
Given:
m∠CDF = (3x + 14)°
m∠FDE = (5x - 2)°
m∠CDE = (10x - 18)°
Since m∠CDE is sum of two angle m∠FDE and m∠CDF.
We can write it as:
m∠CDE = m∠FDE + m∠CDF
Substitute the value:
(10x - 18)° = (5x - 2)° + (3x + 14)°
10x - 18 = 5x - 2 + 3x + 14
Simplify like terms:
10x - 18 = 8x + 12
Subtract 8x on both sides:
10x - 18 - 8x = 8x + 12 - 8x
2x - 18 = 12
Add 18 on both sides:
2x - 18 + 18 = 12 + 18
2x = 30
Divide both sides by 2.

x = 15
Now, finding the value of the angle by substituting the value of x and simplifying it.
m∠CDF = (3 × 15 + 14)° = 59°
m∠FDE = (5 × 15 - 2)° = 73°
m∠CDE = (10 × 15 - 18)° = 132°
Question no. 7:
Given:
m∠LMP = m∠NMP + 11°
m∠NML = 137°
Since m∠NML is sum of two angle m∠LMP and m∠NMP.
We can write it as:
m∠NML = m∠LMP+ m∠NMP
Substitute the value:
137° = m∠NMP + 11° + m∠NMP
Simplify like terms:
137° = 2 m∠NMP + 11°
Subtract 11° on both sides:
137° - 11° = 2 m∠NMP + 11° - 11°
126° = 2 m∠NMP
Divide both sides by 2.

m∠NMP = 63°
Now, finding the value of the angle by substituting the value of m∠NMP and simplifying it.
m∠LMP = 63° + 11° = 74°