Jawabanmu

2013-12-13T20:39:13+07:00
R = | Ax + By + C |
     |  \sqrt{ A^{2} x B^{2}  } |

jd, (0.2 ) + (-1 .-1) + 9
     \sqrt[2]{ 2^{2} } +  1^{2}  }

= 10 /  \sqrt{5}
= 2 \sqrt{5}

semoga membantu :)
2013-12-13T20:44:54+07:00
Jari-jari = jarak pusat ke garis

jarak (x_1,y_1) ke garis ax+by+c=0 adalah d

d=\left |  \frac{ax_1+by_1+c}{ \sqrt{a^2+b^2} }  \right |

jadi
d=\left |  \frac{2(0)-(-1)+9}{ \sqrt{2^2+(-1)^2} }  \right |

d=\left |  \frac{10}{ \sqrt{5} }  \right |

d=\frac{10}{5 } \sqrt{5}

d=2 \sqrt{5}