Persamaan garis lurus yg melalui titik A(-2,0) dan B (3,-10) adalah

melalui titik A (-2, 0) dan B (3, -10)
x1 = -2
y1 = 0
x2 = 3
y2 = -10

(y - y1) / (y2 - y1) = (x - x1) / (x2 - x1)
(y - 0) / (-10 - 0) = (x - (-2)) / (3 - (-2))
y / (-10) = (x + 2) / (5)
---------------------------------------------------- kedua ruas dikali 5
y / (-2) = x + 2
y = -2(x + 2)
y = -2x - 4

atau

2x + y = -4

diket : x1 = -2 , y1 = 0 dan x2 = 3 , y2 = -10
maka,
pers.grs.lurusnya :
y-y1 / y2-y1 = x-x1 / x2-x1
y-0 / -10-0 = x-(-2) / 3-(-2)
y/-10 = x+2 / 3+2
y/-10 = x+2 / 5
-10(x+2) = 5.y
-10x-20 = 5y
y = (-10x-20)/5
y = -2x-4
atau
2x+y = -4
atau
2x+y+4 = 0