Circles Γ1 and Γ2 have centers X and Y respectively. They intersect at points A and B, such that angle XAY is obtuse. The line AX intersects Γ2 again at P, and the line AY intersects Γ1 again at Q. Lines PQ and XY intersect at G, such that Q lies on line segment GP. If GQ=255, GP=266 and GX=190, what is the length of XY?

To find the length of XY, we'll need to use the properties of intersecting circles and their centers.

Let's start by drawing a diagram to visualize the information given:
```
Q
/ \
/ \
/ G \
A-----X B
\ P /
\ /
\ /
Y
```
From the diagram, we can see that triangle AXQ is an isosceles triangle (since XA = XQ, both radii of circle Γ1). Similarly, triangle AYP is also an isosceles triangle (since YA = YP, both radii of circle Γ2).

Let's label the length of XY as d. Since X and Y are the centers of circles Γ1 and Γ2 respectively, the distance XY will be equal to the sum of their radii, which is d.

Now, let's break down the given information:
- GQ = 255
- GP = 266
- GX = 190

We know that GP is a line passing through points G, X, and P. Since GX = 190, we can conclude that XP is 190 as well.

Since triangle AXQ is isosceles, with XA = XQ, we can conclude that angle AXQ is an acute angle (∠AXQ < 90°). This means that angle BXP is the obtuse angle (∠BXP > 90°) since ∠AXQ + ∠BXP = 180°.

Since triangle AYP is also isosceles, with YA = YP, we can conclude that angle AYP is an acute angle (∠AYP < 90°). This means that angle BXA is the obtuse angle (∠BXA > 90°) since ∠AYP + ∠BXA = 180°.

Now, let's use these angles to find the lengths of BQ and AP.

Since angle BXP is obtuse, we can use the Law of Cosines to find BQ:
BQ^2 = BX^2 + XQ^2 - 2 * BX * XQ * cos(BXP)
BQ^2 = 190^2 + 190^2 - 2 * 190 * 190 * cos(BXP)

Since angle BXA is obtuse, we can use the Law of Cosines to find AP:
AP^2 = AX^2 + XP^2 - 2 * AX * XP * cos(BXA)
AP^2 = 190^2 + 190^2 - 2 * 190 * 190 * cos(BXA)

Now, let's find cos(BXP) and cos(BXA):

cos(BXP) = (GP^2 + GX^2 - PQ^2) / (2 * GP * GX)
cos(BXA) = (XP^2 + XA^2 - AX^2) / (2 * XP * XA)

Using the given information:
- GP = 266
- GX = 190
- GQ = 255

We can now substitute these values into the equations to solve for BQ and AP:

BQ^2 = 190^2 + 190^2 - 2 * 190 * 190 * cos(BXP)
BQ^2 = 190^2 + 190^2 - 2 * 190 * 190 * [(GP^2 + GX^2 - GQ^2) / (2 * GP * GX)]

AP^2 = 190^2 + 190^2 - 2 * 190 * 190 * cos(BXA)
AP^2 = 190^2 + 190^2 - 2 * 190 * 190 * [(XP^2 + XA^2 - AX^2) / (2 * XP * XA)]

Finally, we can find d (XY) by summing the lengths BQ and AP:
d = BQ + AP

By substituting the known values, solving the equations, and adding BQ and AP, we can find the length of XY.