tentukan persamaan garis yang melalui titik (-2 ,1 ) dan (1 ,3) pakai cara 1 dn cara 2

cara 1
y-y1 / y2-y1 = x-x1 / x2-x1
y-1 / 3-1 = x+2 / 1+2
y-1 / 2 = x+2 / 3
3y - 3 = 2x + 4
3y = 2x + 4 + 3
3y = 2x + 7

cara 2
m = y2-y1 / x2-x1 = 3-1 / 1+2 = 2/3
y - y1 = m (x - x1)
y - 1 = 2/3 (x + 2)
y - 1 = 2/3x + 4/3
y = 2/3x + 4/3 + 1
y = 2/3x + 4/3 + 3/3
y = 2/3x + 7/3
__________×3
3y = 2x + 7