`d(M,Δ)=|3.2-4.(-1)-12|/\sqrt{3^2+(-4)^2}=2/5`

`⇒ a, ` Sai 

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Ta có : `{(x=2t),(y=2+3t):}`

`⇒3x-2y=6t-4-6t=-4`

`⇔3x-2y+4=0`

`d(M,Δ)=|3.4-2.(-5)+4|/\sqrt{3^2+(-2)^2}=2\sqrt{13}`

`⇒b,` Đúng .

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`c,` Đúng vì `7/7=1/1 \ne -3/12`

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Ta có : `Δ_1: 7x+y-3=0`

Cho `x=0⇒y=3⇒A(0;3)∈Δ_1`

`d(Δ_1,Δ_2)=d(A,Δ_2)=|7.0+1.3+12|/\sqrt{7^2+1^2}=(3\sqrt{2})/2`

`⇒d, ` Sai