What is the equation of the circle with the center (-1,-2) and passes through the point (6,4)?

  (x +1)^2 +(y +2)^2 = 85

Step-by-step explanation:

The equation of a circle with center (h, k) and passing through (a, b) is ...

  (x -h)^2 + (y -k)^2 = (a -h)^2 +(b -k)^2

Filling in your numbers gives ...

  (x -(-1))^2 +(y -(-2))^2 = (6 -(-1))^2 +(4 -(-2))^2 = 49 +36 = 85

  (x +1)^2 +(y +2)^2 = 85

8(-10x+3.5y-7)

8×-10x + 8×3.5y + 8×-7

-80x + 28y - 56

therefore

-80x+28y-56 is the correct answer

hello :

by applying the distributive property :

6 × 4.3 = 6 × ( 4 + 0.3 )

            =   (6 ×   4) + (6 ×   0.3)

            = 24 + 1.8

6 × 4.3 = 25.8