Answer:
This is simple! (Kind of)
Explanation:
First, notice how HJ is tangent. HG is a radius intersecting HJ at H.
This means, (According to some theorem that I forgot the name of) that GHJ is a right angle.
Thus, we can use the 180* in a triangle theorem.
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So, let's solve!
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So, there you go! Nice and simple!
Hope this helps!
Stay Safe!