The angles of a triangle are 2x°, (3x−8)° and (5x−12)°. The greatest angle of the triangle is:
88°
The three angles are 2x, (3x-8), and (5x-12), and they sum to 180: 2x+3x-8+5x-12=180, giving 10x=200, x=20. The largest angle is 5x-12 = 100-12 = 88 degrees.
In the following figure is AC || QR, then Y = ?

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