Answer:
Arc measure of ABC is 283°
Explanation:
We know the total angle of the circle is 360°.
Therefore,
(20y - 11) + (4y +6) + (7y - 7) = 360°
Collecting like terms, we have:
20y + 4y + 7y = 360 + 7 - 6 + 11
31y = 372
Let's divide both sides by 31.
![(31y)/(31) = (372)/(31)](https://img.qammunity.org/2021/formulas/mathematics/high-school/pwpf4t745np6gfk1u3exet3ryp15yy5x6f.png)
y = 12
The arc measure of ABC is the sum of AB and BC. To find the arc measure of ABC, we have:
(4y +6) + (20y - 11)
Collecting like terms, we have:
4y + 20y + 6 - 11
24y - 5
Let's substitute 12 for y
24(12) - 5
288 - 5 = 283°
Arc measure of ABC is 283°