Question

Tolong ya kak
Tidak harus semuanya 5 aja cukup
Terima kasih.....

Answer 1

Verified answer

1)
-3x + 9 = 5y + 3
-3x - 5y = 3 - 9
-3x - 5y = -6

m = -a/b
m = -(-3)/(-5)
m = -3/5

gradien = -3/5

2)
melalui titik (2, -5) dan (4, 6)
m = (y2 - y1) / (x2 - x1)
m = (6 - (-5)) / (4 - 2)
m = 11/2

3)
gradien garis yang melalui titik (5, 2) dan (-5, -3)
m = (y2 - y1) / (x2 - x1)
m = (-3 - 2) / (-5 - 5)
m = (-5) / (-10)
m = 1/2

syarat tegak lurus
m1.m2 = -1
1/2 . m2 = -1
m2 = -2

Persamaan garis melalui titik (-3, 2)
(y - y1) = m(x - 1)
(y - 2) = -2(x - (-3))
y - 2 = -2x - 6
y = -2x - 6 + 2
y = -2x - 4

4)
P(a, 2)
x = a
y = 2

3x - 7y = -26
3a - 7(2) = -26
3a - 14 = -26
3a = -26 + 14
3a = -12
a = -4

Q(3, b)
x = 3
y = b

3x - 7y = -26
3(3) - 7b = -26
9 - 7b = -26
-7b = -26 - 9
-7b = -35
b = 5

a + b = -4 + 5 = 1

5)
titik potong
y = -x + 2
y = x - 1

-x + 2 = x - 1
-x - x = -1 - 2
-2x = -3
x = 3/2

y = x - 1
y = 3/2 - 1
y = 1/2

titik potong (3/2 , 1/2)

Answer 2

Verified answer

Bab Persamaan Garis
Matematika SMP Kelas VIII

1] -3x + 9 = 5y + 3
5y = -3x + 9 - 3
y = (-3/5) x + (6/5)

gradien = m = -3/5

2] m = (y2 - y1) / (x2 - x1)
m = (6 + 5) / (4 - 2)
m = 11/2

5] y = y
    -x + 2 = x - 2
    -x - x = -2 - 2
    -2x = -4
    x = -4 : (-2)
    x = 2

    y = x - 2
      = 2 - 2
      = 0

(2, 0)

7] 3x + 2y = 4, tegak lurus, (2, -1)
    2x - 3y = 2 . 2 - 3 . (-1)  
    2x - 3y = 4 + 3
    2x - 3y = 7

8] (y - y1) / (y2 - y1) = (x - x1) / (x2 - x1)
    (y - 0) / (4 - 0) = (x - 0) / (-2 - 0)
    y / (-2) = 4x
    y = -8x

9] 2x + 3y = 15
    2 . (-a) + 3 . 3 = 15
   -2a + 9 = 15
   -2a = 15 - 9
    a = 6 : (-2)
    a = -3