The general form of the equation of a circle is x2 + y2 + 42x + 38y − 47 = 0. The equation of this circle in standard form is A)
(x - 21)^2 + (y - 19)^2 = 127 B) (x + 21)^2 + (y + 19)^2 = 849 C) (x + 21)^2 + (y + 19)^2 = 851 D) (x - 19)^2 + (y - 21)^2 = 2,209 .The center of the circle is at the point A) (-19, -21) B) (-21, -19) C) (19, 21) D) (21, 19) , and its radius is A) 127^(1/2) B) 849^(1/2) C) 851^(1/2) D) 47 units. The general form of the equation of a circle that has the same radius as the above circle is A) x^2 + y^2 + 60x + 14y + 98 = 0 B) x^2 + y^2 + 44x - 44y + 117 = 0 C) x^2 + y^2 - 38x + 42y + 74 = 0 D) x^2 + y^2 - 50x - 30y + 1 = 0 .
The common way of transforming the general form to the standard form is by using the completing the square method. But there is also a neat shortcut to knowing the h, k and r values right away. The general formula is: x²+y²+Dx+Ey+F = 0 x² + y² + (-2h)x + (-2k)y + (h²+k²-r²) = 0
Solving for h: -2h = 42 h = -21
Solving for k: -2k = 38 k = -19
Solving for r: -47 = (-21)² + (-19)² - r² r = √849
Standard form of given circle is: (x+21)² + (y+19)² = 849
23.8% of 164 is 39.032 so minus that off of 164 and you would've sold 124.968 cars and im guessing you should round so the dealership would've sold 125 cars.
