Question

求满足下列条件的方程,并分别画出他们的图形.1经过点c（-1,1）和D(1,3) ,圆心在X轴上

Answer 1

设圆心A(a,0),AC² = AD²,(a + 1)² + (0 - 1)² = (a - 1)² + (0 - 3)²,a = 2

AC² = r² = (2 + 1)² + (0 -1)² = 10

(x - 2)² + y² = 10

直线X+3y+7=0和3x-2y-12=0的交点A(2,-3)

r² = AC² = (-1 - 2)² + (1 + 3)² = 25

(x + 1)² + (y - 1)² = 25

2x - y = 3,y = 2x - 3

圆心C(c,2c - 3)

AC² = BC²,(c - 5)² + (2c - 3 - 2)² = (c - 3)² + (2c - 3 + 2)²,c = 2

C(2,1)

AC² = r² = (2 - 5)² + (1 -2)² = 10

(x - 2)² + (y - 1)² = 10