What is the arc measure of abc in degrees
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Given:
The measure of arc AB is (4y + 6)°
The measure of arc BC is (20y - 11)°
The measure of arc AC is (7y - 7)°
We need to determine the measure of arc ABC.
Value of y:
The value of y is given by
[tex]m \widehat{AB}+m \widehat{BC}+ m \widehat{AC}=360[/tex]
Substituting the values, we get;
[tex]4y+6+20y-11+7y-7=360[/tex]
Adding the like terms, we have;
[tex]31y-12=360[/tex]
Adding both sides of the equation by 12, we have;
[tex]31y=372[/tex]
[tex]y=12[/tex]
Thus, the value of y is 12.
Measure of arc ABC:
The measure of arc ABC can be determined by adding the measure of arc AB and arc BC.
Thus, we have;
[tex]m \widehat{ABC}=m \widehat{AB}+ m \widehat{BC}[/tex]
[tex]m \widehat{AB}+m \widehat {BC}=4y+6+20y-11[/tex]
[tex]=24y-5[/tex]
Substituting y = 12, we get;
[tex]m \widehat{AB}+m \widehat {BC}=24(12)-5[/tex]
[tex]=288-5[/tex]
[tex]m \widehat{AB}+m \widehat {BC}=283^{\circ}[/tex]
Thus, the measure of arc ABC is 283°