What is the measure of angle c?

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3 Answers
May 19, 2018

59 degrees

Explanation:

Since ABCD is a cyclic quadrilateral,

then

#angle ABC + angle ADC = 180#
(opposite angles in cyclic quadrilateral are equal to 180 degrees)

#2x+3+4x+3=180#
#6x+6=180#
#6x=174#
#x=29#

Since #angle BCD = 2x+1#, then you just sub in #x=29#

ie. #angle BCD = 2(29)+1 = 59#

May 19, 2018

#color(blue)(59^@)#

Explanation:

Opposite angles in a cyclic quadrilateral are supplementary.

So:

#/_B+/_D=180^@#

#/_B+/_D=(2x+3)+(4x+3)=180^@#

# \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \=6x+6=180#

#x=(180-6)/6=29^@#

#/_C=2x+1=2(29)+1=59^@#

May 19, 2018

Measure of #color(indigo )(hat C = 59^@#

Explanation:

Given #hatB = 2x + 3, hat C = 2x + 1, hat D = 4x + 3#

To find measure of #hat C#

It’s a cyclic quadrilateral and hence sum of opposite angles equals #180^@#

i. e. #hat A + hat C = hat B + hat D = pi^c = 180^@#

#hat B + hat D = 2x + 3 + 4x + 3 = 180^@#

#6x + 6 = 180#

#x = (180 - 6) / 6 = 29^@#

#hat C = 2x + 1 = (2*29 + 1) = 59^@#