tolong jawab nomor 7 - 10

7.
p = 2q + 3
5p - 2q + 1 = 0

5p - 2q + 1 = 0
5p - 2q = - 1
5(2q + 3) - 2q = - 1
10q + 15 - 2q = - 1
8q = - 1 - 15
8q = - 16
q = - 2

p = 2q + 3
p = - 4 + 3
p = - 1

8.
x - 2y + 1 = 0
2x + 3y = 12

x - 2y + 1 = 0
x - 2y = - 1
x = - 1 + 2y

2x + 3y = 12
2(- 1 + 2y) + 3y = 12
- 2 + 4y + 3y = 12
7y = 12 + 2
7y = 14
y = 2

x = - 1 + 2y
x = - 1 + 4
x = 3

9.
2m - 3n = 1
3m - 2n = 4

2m - 3n = 1|× 2
3m - 2n = 4|× 3

4m - 6n = 2
9m - 6n = 12
_________—
- 5m = - 10
m = 2

2m - 3n = 1
4 - 3n = 1
- 3n = 1 - 4
- 3n = - 3
n = 1

10.
4a + 3b = 6
2b - 3a = - 13

2b - 3a = - 13
- 3a + 2b = - 13

4a + 3b = 6|× 2
- 3a + 2b = - 13|× 3

8a + 6b = 12
- 9a + 6b = - 39
____________—
17a = 51
a = 3

4a + 3b = 6
12 + 3b = 6
3b = 6 - 12
3b = - 12
b = - 4

Maaf Kalau Salah