How to use figure function(python, matplotlib). Draw multiple graphs

import matplotlib.pyplot as plt
import numpy as np # Defined to use the arange function

x=np.arange(10)
y1=x*2
y2=x*x

plt.figure()

plt.subplot(2,1,1) # Defined first in 2 rows and 1 column graph
plt.plot(x, y1)

plt.subplot(2,1,2) # Defined second in 2 rows and 1 column graph
plt.plot(x, y2)

plt.show()

x=np.arange(10)
y1=x*2
y2=x*x

plt.figure()
plt.plot(x, y1)

plt.figure()
plt.plot(x, y2)

plt.show()