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37 votes
37 votes
Angle A and angle B are vertical anglesIf m angle A=(5x-3)^ and m angle B=(4x+21)^ then find the measure of angle A .

[PLEASE HELP]

User Eloi Navarro
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2.7k points

2 Answers

22 votes
22 votes

Answer:

78

Explanation:

5x3+4+21=78

User Steve Knight
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3.1k points
12 votes
12 votes

Answer:

m<A=117°

Explanation:

Based on the given from the problem, we know that angle A and angle B are vertical angles

Vertical angles are congruent; they have the same value.

we know that the measure of angle A is (5x-3)° and the measure of angle B is (4x+21)°

since we know they are congruent via vertical angles theorem, we can make the two values equal to each other

5x-3=4x+21

add 3 to both sides

5x=4x+24

subtract 4x from both sides

x=24

we found the value of x. However, the question asks for the value of angle A, which is (5x-3)°

we substitute our known value to find the value of angle A

m<A= (5*24-3)°

m<A=(120-3)°

m<A=117°

the measure of angle A is 117°

Hope this helps!

User QArea
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3.7k points