​ Quadrilateral ABCD ​ is inscribed in a circle. What is the measure of angle A?

1 Answer
Write your answer here...
Start with a one sentence answer
Then teach the underlying concepts
Don't copy without citing sources
preview
?

Answer

Write a one sentence answer...

Answer:

Explanation

Explain in detail...

Explanation:

I want someone to double check my answer

Describe your changes (optional) 200

4
Y Share
May 12, 2017

Answer:

#mangleA=77^@#

Explanation:

Consider the property of cyclic quadrilaterals for which opposite angles are supplementary, then:
#mangleA+mangleC=180^@#

Since we are given that #mangleA=(2x+9)^@# and #mangleC=(3x+1)^@#, we can substitute to find the value of #x#:
#2x+9+3x+1=180#
#5x+10=180#
#5x=170#
#x=34#

Now, we can substitute in the above value of #x# to find #mangleA#:
#mangleA=(2x+9)^@=(2*34+9)^@=77^@#

Therefore, the #mangleA=77^@#

Was this helpful? Let the contributor know!
1500