What is the center this circle?
x2 + y2 + 6x – 10y + 18 = 0

(- 3, 5 )

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 - 10y + 18 = 0 (collect x terms and y terms together )

x² + 6x + y² - 10y + 18 = 0 ( subtract 18 from both sides )

x² + 6x + y² - 10y = - 18

Use the method of completing the square on both the x and y terms

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

x² + 2(3)x + 9 + y² + 2(- 5)y + 25 = - 18 + 9 + 25, that is

(x + 3)² + (y - 5)² = 16 ← in standard form

with centre = (- 3, 5 ) and r = = 4

step-by-step explanation:

infinity is the answer

step-by-step explanation:

assume that you have 3 different side lengths.   apply the pythagorean theorem here:   square each of the two shortest sides; call them a and b, so that their squares are a² and b².   also square the longest side, calling the result c².

now, if a² + b² = c² is true, the triangle is a right triangle; otherwise it is not a right triangle.