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URGENT PLEASE HELP!!!!!!!!!!!! Quadrilateral ABCD ​ is inscribed in a circle.

What is the measure of angle A?



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m∠A= ____°

URGENT PLEASE HELP!!!!!!!!!!!! Quadrilateral ABCD ​ is inscribed in a circle. What-example-1
User Bicarlsen
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2 Answers

2 votes
Opposite angles in a cyclic quadrilateral are equal to 180°.
Therefore,
(4x+5) + (x+15) = 180°
Collect like terms
4x+x+5+15 = 180°
5x+20 = 180
5x = 180-20
5x = 160

x = (160)/(5)

x = 32

A = 4x+5
A = 4(32)+5
= 128+5
= 133°
User Yousri
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8.5k points
5 votes

I got 3.33 because I just set the problem up as

4x+5=x+15

and then I did

4x-x=3x

and then I did

15=3x+5

and then

15-5=10

and then

3x=10

then

10÷3=3.33

User Smiksky
by
7.8k points