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Circles pls help decent amount of points ​

Circles pls help decent amount of points ​-example-1
User Ose
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Recall that with inscribed angles, they equal half of the arc they create.

Knowing this, take a look at Angle B. Notice that it's two lines are on the diameter? This means that the arc created is 180 degrees. Because it's an inscribed angle, we know that it's 90 degrees.

Also recall that the sum of all angles in a triangle equal 180 degrees.

Knowing this, we can add up all the angles:
(2x + 2) + 9x + 90 = 180

Simplify:
11x + 92 = 180

Subtract:
11x = 88

Divide:
x = 8

Now that we know the value of x is 8, we can input that into the equation of angle 1 in order to solve the question:
2x + 2 = 2(8) + 2

2(8) + 2 = 16 + 2 = 18

Angle 1 is 18 degrees.
-T.B.
User Wolfgang
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