Solved Examples and Worksheet for Finding Unknown Angle Using an Equation

Q1What is the value of n?


A. 20°
B. 25°
C. 30°
D. 15°

Solutions
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Step: 1
To find the value of n, add the two adjacent angles given in the figure and set the sum equal to 65°.
Step: 2
45° + n = 65°
Step: 3
Now, solve for n.
Step: 4
n + 45° - 45° = 65° - 45°
  [Subtract 45° from both sides]
Step: 5
n =20°
Step: 6
Therefore, the value of n is 20°.
Correct Answer is :   20°
Q2What is the value of y?


A. 55°
B. 50°
C. 45°
D. 35°

Solutions
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Step: 1
To find the value of y, add the two adjacent angles given in the figure and set the sum equal to 115°.
Step: 2
70° + y = 115°
Step: 3
Now, solve for y.
Step: 4
y + 70° - 70° = 115° - 70°
  [Subtract 70° from both sides]
Step: 5
y = 45°
Step: 6
Therefore, the value of y is 45°.
Correct Answer is :   45°
Q3What is the value of k?


A. 140°
B. 130°
C. 145°
D. 135°

Solutions
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Step: 1
To find the value of angle k, add the two adjacent angles in the given figure.
Step: 2
k = 75° + 65° = 140°
Step: 3
Therefore, the value of k is 140°
Correct Answer is :   140°
Q4What is the value of b?


A. 140°
B. 155°
C. 145°
D. 135°

Solutions
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Step: 1
To find the value of angle b, add the two adjacent angles in the given figure.
Step: 2
b = 50° + 95° = 145°
Step: 3
Therefore, the value of b is 145°.
Correct Answer is :   145°
Q5What is the value of k?

A. 40°
B. 230°
C. 35°
D. 30°

Solutions
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Step: 1
To find the value of k, add the two adjacent angles given in the figure and set the sum equal to 130°.
Step: 2
100° + k = 130°
Step: 3
Now, solve for k.
Step: 4
k + 100° - 100° = 130° - 100°
  [Subtract 100° from both sides]
Step: 5
k =30°
Step: 6
Therefore, the value of k is 30°.
Correct Answer is :   30°
Q6What is the value of p?


A. 60°
B. 45°
C. 50°
D. 10°

Solutions
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Step: 1
To find the value of angle p, add the two adjacent angles in the given figure.
Step: 2
p = 20° + 30° = 50°
Step: 3
Therefore, the value of p is 50°
Correct Answer is :   50°
Q7What is the value of q?


A. 25°
B. 45°
C. 155°
D. 35°

Solutions
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Step: 1
To find the value of q, add the two adjacent angles given in the figure and set the sum equal to 95°.
Step: 2
60° + q = 95°
Step: 3
Now, solve for q.
Step: 4
q + 60° - 60° = 95° - 60°
  [Subtract 60° from both the sides]
Step: 5
q = 35°
Step: 6
Therefore, the value of q is 35°
Correct Answer is :   35°
Q8What is the value of y?


A. 50°
B. 110°
C. 60°
D. 120°

Solutions
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Step: 1
To find the value of angle y, add the two adjacent angles in the given figure.
Step: 2
y = 85° + 35° = 120°
Step: 3
Therefore, the value of y is 120°.
Correct Answer is :   120°
Q9What is the value of q?


A. 115°
B. 65°
C. 75°
D. 55°

Solutions
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Step: 1
To find the value of q, add the two adjacent angles given in the figure and set the sum equal to 170°.
Step: 2
105° + q = 170°
Step: 3
Now, solve for q.
Step: 4
q + 105° - 105° = 170° - 105°
  [Subtract 105° from both sides]
Step: 5
q = 65°
Step: 6
Therefore, the value of q is 65°.
Correct Answer is :   65°

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