i think it 30 but I could be wrong
The 2 blue parallel lines because they are parallel :)

=

Multiply both sides by 15
6 =

Multiply both sides by c
6c = 30 Divide both sides by 6
c = 5
Answer:
y=5/2
Step-by-step explanation:
The arc length of the semicircle is 5π units
<h3>Calculating length of an arc</h3>
From the question, we are to calculate the arc length of the semicircle
Arc length of a semicircle = 1/2 the circumference of the circle
∴ Arc length of a semicircle = 1/2 × 2πr
Arc length of a semicircle = πr
Where r is the radius
From the given information,
r = 5
∴ Arc length of the semicircle = 5 × π
Arc length of the semicircle = 5π units
Hence, the arc length of the semicircle is 5π units
Learn more on Calculating length of an arc here: brainly.com/question/16552139
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