1:

a = (1 / 9) * b ** 3 - 6.4 * (b + 8) + (3 / 4) * b

2:

d = (1 / 7) * a ** 3 * b - 2 * a * b ** 2 * (a + b)

3:

q = (3 * a ** 3 - 2 * a * b + b ** 2) / (2 * a * (3 * a - b))

4:

k = x ** 3 - 4 * x * y * (x + y ** 2)

5:

h = abs(v + 1.7) * (2 * v + 3)