Question

escrever a equacao da circunferencia cujo centro e o ponto -3,-5 e raio igual a 7

Answer 1

C( - 3 , - 5 )         r = 7
     xa   yx

( x - xa )² + ( y - ya )² = r²
( x - (- 3) )² + ( y - ( - 5) )² = 7²
( x + 3 )² + ( y + 5 )² = 49
x² + 6x + 9 + y² + 10y + 25 = 49
x² + y² + 6x + 10y + 9 + 25 = 49
x² + y² + 6x + 10y + 34 = 49
x² + y² + 6x + 10y + 34 - 49 = 0
x² + y² + 6x + 10y - 15 = 0