tolong jawab ya, pr ekonomi

1. Qd = 150-2,5P
50 = 150-2,5P
2,5P = 150-50
2,5P = 100
P = 40
Jadi Pd = 40

2. P = -4Q+120
40 = -4Q+120
4Q = 120-40
4Q = 80
Q = 20
Jadi barang yg diminta sebanyak 20 unit

3. Q = 5P-20
40 = 5P-20
-5P = -20-40
-5P = -60
P = 12
Jadi harganya adalah Rp. 12
Semoga membantu