OK Google diketahui garis 4x-ay=5 dan 3x+(a+1)y=10 saling tegak lurus tentukan a. nilai a b. titik potong kedua garis c. persamaan garis yang melalui titik o(

4x -ay = 5
ay = 4x - 5
y = (4x - 5) a
y = (4/a)x - 5/a, misal m1 = 4/a
3x + (a+1)y = 10
(a+1)y = -3x + 10
y = (-3x + 10) /(a+1)
y = (-3/ (a + 1)x + 10( a + 1)
misal gradien m2 = -3/ (a+1), karena garis tegak lurus maka m1.m2 = -1.
4/a = -3 / (a +1)
4(a + 1) = -3a
4a + 4 + 3a = 0
7a = -4
a = -4/7
Jadi y1 = (4x -5) / (-4/7)
y1 = -7(4x -5)/4
y2 = (-3x + 10) / (-4/7+1)
y2 = (-3x + 10 ) / (3/7)
y2 = 7(-3x + 10)/3
y1 = y2
-7(4x-5) = 7(-3x + 10)/3
-3(4x-5) = -3x + 10
-12x + 15 = -3x + 10
-12x +3x = 10-15
-9x = -5
x = 5/9
y1 = -7(4x -5)
y1 = -7(4.5/9 - 5)
y1 = -7(20/9 -5)
y1 = -7(-25/9)
y1 = 175/9
y1 = 19 4/9
Jadi titik potong kedua garis ( 5/9, 19 4/9)