X2+y2-6x+2y-39=0 what is the radius and the center

(centre = (3, - 1 ) and radius = 7

Step-by-step explanation:

The equation of a circle in standard form is

(x - h)² + (y - k)² = r²

where (h, k) are the coordinates of the centre and r is the radius

Given

x² + y² - 6x + 2y - 39 = 0 ( collect x/ y terms and add 39 to both sides )

x² - 6x + y² + 2y = 39

Using the method of completing the square

add ( half the coefficient of the x/ y terms )² to both sides

x² + 2(- 3)x + 9 + y² + 2(1)y + 1 = 39 + 9 + 1

(x - 3)² + (y + 1)² = 49 ← in standard form

with centre (3, - 1 ) and r = = 7

pentagon

step-by-step explanation:

the coordinates   a(5, -2), b(3,-1),c(-4,-4) d(-3,8) and e(-1,4) forms the vertices of the polygon when they are connected in order.

in order to classify that which polygon is it with the given coordinates, first count the number of vertices and then count the number of sides it can make with these vertices.

since, the given coordinates have five vertices, therefore, it will make five sides. moreover, pentagon is regular in nature therefore it will be convex.

now, a polygon with five sides is known as pentagon, therefore, the given polygon is the pentagon.

i think the length is 12 and the width is 17