Tentukan persanaan garis yg melalui titik C ( 4,-2 ) D ( -6, -12 )
persamaan garis lurus (PGL)
melalui 2 titik (4,-2) dan (-6,-12)
y – y1/y2 – y1 = x – x1/x2 – x1
y – (-2)/-12 – (-2) = x – 4/-6 – 4
y + 2/-12 + 2 = x – 4/-10
y + 2/-10 = x – 4/-10
-10(x – 4) = -10(y + 2)
-10x + 40 = -10y – 20
-10x = -10y – 20 – 40
-10x = -10y – 60
-10x + 10y – 60 = 0
10x – 10y + 60 = 0
atau
10x = 10y + 60
x = y + 6