Given that circle (X-2) 2 + (y + 3) 2 = 13 and circle (x-3) 2 + y2 = 9 intersect at two points a and B, the equation of the vertical bisector of string AB is______ ．

Given that circle (X-2) 2 + (y + 3) 2 = 13 and circle (x-3) 2 + y2 = 9 intersect at two points a and B, the equation of the vertical bisector of string AB is______ ．

∵ circle (X-2) 2 + (y + 3) 2 = 13 and circle (x-3) 2 + y2 = 9 intersect at two points a and B, and ∵ A and B are symmetrical about the straight line passing through the center of two circles. The equation of circle center C1 (2, - 3), C2 (3, 0) and ∵ straight line C1C2 is y − 0 − 3 − 0 = x − 32 − 3, which is reduced to 3x-y-9 = 0, so the answer is: 3x-y-9 = 0

How many people clean the glass? How many people clean the glass? How many pieces of glass do you have

There are x people
6X=2×4+5（X-2）+12
6X=5X+10
X=10
6X=60
There are 10 people and 60 pieces of glass

If the equations X & # 178; + ax + B = 0 and X & # 178; + BX + a = 0 about X have only one common root, then they have (a + b) 2014 power
______

Let this common root be m, then:
m+am+b=0;---------------(1)
m+bm+a=0.---------------(2)
(1) (2) am BM + B-A = 0, i.e. (a-b) M = a-b
Two equations have a common root, so: A-B ≠ 0. (Note: A-B = 0, two equations are the same, there will be two common roots!)
The result is: 1 + A + B = 0
So, a + B = - 1, (a + b) 2014 = (- 1) 2014 = 1