Answer:
D
Explanation:
7 - z = 3 + z + 4 - 2z
7 - 3 - 4 = z - 2z + z
0 = 0 (Infinitely many solutions)
5(a + 4) - 15 = -5(a - 1)
5a + 20 - 15 = -5a + 5
5a + 5a = 5 - 20 + 15
10a = 40
10a/10 = 40
a = 4
(one solution)
-2d + 4d - 4 = 5 + 3(d - 3)
2d - 4 = 5 + 3d - 9
2d - 3d = 5 - 9 + 4
- d = 0
d = 0
(one solution)
-11(n - 2) + 8(n + 1) = -3(n + 10)
-11n + 22 + 8n + 8 = -3n - 30
-11n + 8n + 3n = -30 - 22 - 8
0 = -60
(no solutions)