1.tentukan persamaan garis lurus yg melalui titik (0-4) dan beragadiem 3 !
2.Tentukan persamaan garis yg melalui titik (1,4) dan (2,-1)
Tolong dong dijawab yg benar
1) y-y1=m(x-x1)
y-4 =3(x-0)
y-4 =3x
Y. =3x+4
2) y-y1/y2-y1 = x-x1/x2-x1
y-4/-1-4. = x-1/2-1
Y-4/-5. = x-1/1
1(y-4). = -5(x-1)
1y-4. = -5x+5
-5x-1y =5+4
-5x-1y =9
2.Tentukan persamaan garis yg melalui titik (1,4) dan (2,-1)
Tolong dong dijawab yg benar
y-4 =3(x-0)
y-4 =3x
Y. =3x+4
2) y-y1/y2-y1 = x-x1/x2-x1
y-4/-1-4. = x-1/2-1
Y-4/-5. = x-1/1
1(y-4). = -5(x-1)
1y-4. = -5x+5
-5x-1y =5+4
-5x-1y =9
Penjelasan dengan langkah-langkah:
1) (0, -4) gradien m = 3
x1 y1
rumus :
y - y1 = m (x - x1)
y - (-4) = 3 (x - 0)
y + 4 = 3x - 0
y + 4 = 3x
y = 3x - 4
2) (1, 4) (2, -1)
x1 y1 x2 y2
rumus :
y - y1 x - x1
----------- = -----------
y2 - y1 x2 - x1
y - 4 x - 1
---------- = --------
-1 - 4 2 - 1
y - 4 x - 1
---------- = --------
-5 1
1 (y - 4) = -5 (x - 1)
y - 4 = -5x + 5
y = -5x + 5 + 4
y = -5x + 9